Power Supply Basic Facts.

[XZEMi]

Fact a computer runs cooler and is less likely to present errors with a good quality power supply.

Fact anything over 850 watts is complete hype with the exception of dual processor server systems or systems with more than two graphics cards.

Fact processors and video cards once again are becomming more energy efficient with the exception of AMD at the time of this posting but AMD is soon to follow. This means less power is required.

Fact gold rated power supplies run cooler than bronze rated and platinum is just a way to charge you more for little differance over gold.

Fact Seasonic has always been a well regarded power supply company amongst all the new brands.

Fact Corsair are likely rebranded slightly modified Seasonics.

Fact Antec made good power supplies then started making worse ones but are now back in the game making pretty decent stuff since Delta Electronics now makes their power supplies.

[Zka17]

Wow, man! And you got these from your 112 years (from your basic info) of experience?! :cool:

"Fact a computer runs cooler and is less likely to present errors with a good quality power supply." I agree with the "...is less likely to present errors with a good quality power supply." part, but I have some thoughts about "Fact a computer runs cooler..." - this depends on the case design. Most of the modern cases are design in a way that the psu has it's own air circulation: getting air from outside (bottom) and exhausting outside (rear). In this case, how the computer run hot, even with a hot psu?!

"Fact anything over 850 watts is complete hype with the exception of dual processor server systems or systems with more than two graphics cards." - pretty much, I agree. But, hey, do you know that feeling to know that you have more reserves? Specially, when you're planning to have an upgrade - like put in more graphic cards, OC, get more fans, or more pumps for your WC.

"Fact processors and video cards once again are becomming more energy efficient with the exception of AMD at the time of this posting but AMD is soon to follow. This means less power is required." - Well, see above! Heavy OC and/or multiple high-end graphic cards still require more power...

"Fact gold rated power supplies run cooler than bronze rated and platinum is just a way to charge you more for little differance over gold." - I would be interested in founding out how did you get to this conclusion! As I said above, why is the psu temp matter if it has completely isolated airflow from the rest of the system? Gold rated psus are higher quality than bronze rated ones (at least that's the idea making them), as platinum rating is higher than the gold one - it depends on your pocket which one you will get. But let me tell you something! You may have even the highest platinum rated psu if you don't have proper power protection (like a good ups)...

"Fact Seasonic has always been a well regarded power supply company amongst all the new brands." - OK, so?

"Fact Corsair are likely rebranded slightly modified Seasonics." - So, what's the problem? If "Seasonic has always been a well regarded power supply company amongst all the new brands."

"Fact Antec made good power supplies then started making worse ones but are now back in the game making pretty decent stuff since Delta Electronics now makes their power supplies." - If you say so... Never had any experience with Antec psus, but will keep this in my mind, in case i will need an other psu.

[DaemonCantor]

Well I'm glad to have read this and now I guess all of the years I've been a computer Technician working in just about all phases is meaningless due to the fact that all I've ever created or helped in creating is nothing but a fabrication for the masses.

Truth...AMD has been creating Power Efficient Parts for over 8 years now with better Power Curves than nVidia.
If you control the Power input with a good Quality UPS your system will run better and smother with less parts burning out and less system error(BSOD's) and others plus consume about 5% to 10% less power. Proven 1 source: http://3dfs.com/technology/white-paper but articles on this can be found all over the place and has been talked about since 1986 when I worked for Mac Donald Douglas Aircraft as part of the IT Department in R&D.
Seasonic has been a fairly good PSU supplier but there are very few companies purchasing from them due to COST. but getting a Good Quality Single Rail PSU is always worth the time it takes to do the research.
Cooling...A PSU no matter what brand or Quality will create Heat it's called Physics but if you run a PSU at only 50% your going to create less heat because the Electronics are running more Efficiently that at 80% which also means that when you combine the Power needs of ALL Main components which comes up to around 600watts on a Modern System your going to need a 1200watt PSU to get the 50% usage and then you start adding more Drives, Fans, Expansion Cards this value goes up. but the best case efficiency mark is around the 70% mark which still puts PSU requirements at over 850watts.
Final point is 'If your saying to purchase Good Quality Components then you are very correct' and I applaud you in this and everyone should look at what they are spending their money on.

[Zka17]

DaemonCantor: don't worry, your efforts were NOT meaningless! :D

"A PSU no matter what brand or Quality will create Heat it's called Physics" - you're absolutely right! All I was saying is that heat won't get inside the case (at least with today's designs), so won't add anything to whole system's temperatures. However, blocking the proper vent of a psu, that will be hot! - not only the psu, but on your wallet too...

Let's face it, 600W "on a Modern System" is a little bit overkill... Or not? Running stress tests (Prime95, Furmark) on a Core i7-980X at 4.6GHz, an Asus DirectCu II TOP at 1GHZ, an H100 pump and 7 fans (plus an SSD, HDD - but these anyway don't count during stress testing) barely reaching 450W measured on the ups (monitor, modem also connected to it)... This is meaning 450W at full load. I could drop in my GTX480s in 3 way SLI, but that would not be anymore a "modern system", I guess... So, for this system a 850W psu would be just fine - right?

But, as I said earlier, I like to have reserves - I'm running now an AX1200... And I think a lot of people here actually would agree with me - specially because of those GTX480s (they are really power-hungry).

I completely agree: "Good Quality Components" with a "Good Quality UPS"!

[DaemonCantor]

Yes I know that a 600watt system is a little more than typical but then again I can't start my CHIVF with 1 HD, 1 Optical, and 1 GPU with less than 350watts and that's with a low end GPU at that....My system uses around 600watts with the ATI Radeon HD5870 and that's about normal now days unless you get into Intel and some of their CPU's are only 90watts where as mine is 145watts baseline. On the Price Per Watt Intel still has AMD beat but hopefully not for long. So 600watts isn't that far off maybe only 10% and I'm just getting by with a 975watt PSU truthfully and because of the load I'm expecting to need a replacement within a year.

As to the heat being expelled Hell Yes the newer Cases expels heat and manage Heat Zones way better than even 2 years ago plus the fact as you put it the PSU Thermal Zone is removed with Bottom Mounted PSU's now...Good Catch there.

[oneawesomeseabee]

Wow .. i have to say to the person that started the thread .. hmmmm. I have 1200 watt power supply for my system .. go to a good wattage calculator .. and with my system i will need 1100 when i install the liquid cooling. So i have to say .. 800 watts is a waste. I guess my math must be all wrong. lol. Read info on profile. Plus before i upgraded from a 4 core amd to an 8 core fx 850 watts was not enough to get me over 4.2 ghz on my6 6 core I had. To me .. more power means (especially from an overclockers standpoint) more stable power .. ie less spikes in voltage. I think psus are the problem when overclocking along with heat .. which makes it difficult to diagnose. But again .. More power means a more stable system which makes for easier diagnosis when first starting to overclock. I hope all take this post with respect (which is the way it is intended).

Richard

[Zka17]

Well, oneawesomeseabee, would you please share the "good wattage calculator" you used to get those values? Did you effectively measure how much power your system draws? I mean, not by calculators (how much it should draw), but real measuring tools (how much is actually drawing)? It was long time age, when I used AMD-based system, but I doubt that with that configuration you can draw 1100W...

[DaemonCantor]

I don't, the AMD Dozer 6 core is rated at 185watts, the CHVF or CHVT takes 225 watts, plus 80watts to start an HD and then they drip to around 45watts idling then add 45watts for your standard Optical Drive...Hmmmm lets see that's 535watts alone with out a GPU and I don't care if it has external Power or not they all start at 185watts so if you add that your looking at 720watts just to start the system and Idle does bring it down but even them it will depend on how much power savings the idle mode gives you ie: Intel system probably idles at around 450wats where as a Dozer idles at around 600watts (mostly due to the CPU). Now you change up to like an ATI Radeon HD5870 which AMD even states is over 250watts now your pushing between 700watts at idle to 900 watts running at full tilt then add a second 5870 to the mix in Crossfire and you've easily broken 1000watts of power. People think that the CPU is the biggest hog on a system but in reality it's the North Bridge and South bridge that are they both run at about 100watts each plus the Sound Chips which are another Power Sink with the AD and DA converters....where as on the Drives it's the motors that pull all of the juice...

[XZEMi]

Hmm I did not figure people would actually debate my simple post to help those who would have no idea what power supply to get and just go buy the 1300 watt one because its the biggest they can get. Oh well just a little something to consider if you buy quality you get quality but it is application dependant. For instance you dont want a seasonic gold modular power supply in a small form case because it will not always run its fan and evacuate the heat. You would be better off getting a cheaper supply that has a fan constantly running. And yeah overclocking I managed to get 4.2 ghz+ with the FX8120 on a 430watt corsair ps and gtx560ti. I dont have the video but if enough people are interrested I can probably make one.

[DaemonCantor]

Poor lit'el Corsair....I hope he didn't abuse you too much....yea you probably did! you were using the OverCurrent circuit which will give up to an additional 200watts depending on PSU design and yes I've seen an Antec Earth Watt 350 put out 600watts but it only held together for about an hour and then it fried. and I couldn't duplicate your feat with out Hardware damage...

[Zka17]

DaemonCantor, something is wrong with your calculations...

XZEMi's AMD FX-8150 is rated at 125W, but yes, during OC that would go higher.
But this: "CHVF or CHVT takes 225 watts" - that's not right, my friend :eek:
Check this review: http://www.guru3d.com/article/asus-crosshair-iv-formula-review/8

What you put there, that may be the whole system's consumption... then XZEMi is very much right about his values!

Also, not sure from where did you get the 80W/45W for an HD (what is this, the HDD?!), and 45W for a standard Optical Drive...

[DaemonCantor]

Ok first reread the post I stated Start Up power not running or Idling that came next and was a much lower total. and the 225 came from testing with my CHIVF which is one generation back on the chipset but there is no stated power draw change from AMD Developer Network.
Also the review you pointed to is the CHIVF but it's not with the Dozer but the Phenom II x4 and x6 also read further on that same link and you'll notice quickly that they were just showing real world wattage for the CPU the GPU wasn't stressed and was only in low power idle mode of which the 5870 is know to idle at low wattage but this link will show the Difference with it: http://www.tomshardware.com/reviews/radeon-hd-5870,2422-20.html, and now you can see what I was talking about and why the measurements for the GPU wasn't included in the totals from your link that wattage would have been through the roof when you add that to it plus all of the other components as well. So now that were done with questioning why and know that that was only the CPU wattage measurements can we get back on track here?

[Zka17]

You're right, DaemonCantor, I did get lost a little bit... sorry for that! I started to argue about oneawesomeseabree's system (post #7) - and he has the components I was posting temps for. For that system 1100W is too much!

Also, XZEMi's system is closer to oneawesomeseabree's (post #9), so I can accept his results - completely fit to that review I posted in #11.

My mistake was that i was not careful and didn't observed your hardwer's specs. Again, sorry for that!

Compensating my mistake, checked up the CHVF reviews... Here is one with both cpu's debated here: http://www.legitreviews.com/article/1748/12/ Although they used a Radeon HD 6950... - which actually is more power hungry than the HD 5870 (with 12W, check: http://www.hwcompare.com/6132/radeon-hd-5870-vs-radeon-hd-6950/)! So, the CHVF eats 264W with the Phenom II X6, and 282W with the FX-8150... - these are total system consumptions! And yes, only the cpu got stressed.

On the link you provided, they are showing the power consumption, for the whole system as well, as being max 354W for one HD 5870 (stressed with Furmark) - we are not arguing here with the SLI or Crossfire systems as we all agreed already that they need more power.

Based on these, I cannot agree with your statement: "Dozer idles at around 600watts (mostly due to the CPU)" That's maybe the max power consumption for the system you described and not the idle one... As such a 850W psu would be just fine with that system (one Dozer with one 5870). Also, XZEMi's values are also fine, he didn't overloaded his psu.

And don't worry about "...can we get back on track here?" - we were all the time on the track! :cool: Right, XZEMi?

[DaemonCantor]

I just finnished reading a newer review at: http://www.tomshardware.com/reviews/4tb-3tb-hdd,3183-15.html, which shows a lot lower Hard Drive wattage level than they did just a year ago and it surprised the hell out of me. so I guess that HD's are not using Vast amounts of power they were using now and that has dropped to under 10watts finally. A year ago they were showing between 45 to 60 watts at Idle and this seemed correct at the time because the old PATA drives were major Power Hogs.... and ran in about the same zones. Thank you Zka17 for making me go and look up some newer facts.

[Zka17]

Well, my friend, I did hope that "HD" is not Hard Drive... Hard drive wattages were below 10W for several years now: http://www.silentpcreview.com/article904-page2.html :cool:

[chrsplmr]

... Member's Objection Withdrawn ...

+Kipper.

[Zka17]

ooops, just observed that this post is no longer serves it's initial purpose - withdrawn too

[Kipper]

I find this thread interesting and informative and refreshing to see some talk about what I think is the most important component of any system.

My experience has shown me that the PSU is often the least thought out component on anyone's shopping list.

Looking forward to some continued conversation on a most important topic.

Thank guys

[Zka17]

Thank you Sir!

+1 vote for "...I think is the most important component of any system."

[chrsplmr]

Hey thats what i said ...
One does not have to be wrong for the next to be right. Thats how the
third comes up with the new answer and better question.

Yes.Arguing is prohibited. Im a Member. Facts Not Flaps.
Personal Member Attacks or Commentary except as friends. - Prohibited.
Just a friendly, hey guys you are confusing 'we' simple folk..

btw .. i have read them All .. 1000's ... i'm obsessed .. Welcome to ROG.

Thanks Kipp ... so .. about 850 watt ... ok.c.

[Zka17]

"One does not have to be wrong for the next to be right. Thats how the third comes up with the correct answer." - man, i love this! May I quote you sometimes? :cool:

"Arguing is prohibited."??!! - What do you mean by this? Why it would be prohibited?! It's the only way to have a civilized, constructive and fun conversation...

"Personal Member Attacks - Prohibited" - 100% agree! Who was attacking who here? We are just discussing/arguing... :D

[chrsplmr]

Hey bro ... Of course yes to the quote .. i have extras ..

The rest has been established in this thread as moot.
Continue. If I was wrong. I got over it...

I take nothing personal except the friendship...

[[[[[ 1st ... I see the gentlemans position and understand why he believes this..
2nd....I have always believed in this position as I understand it.
3rd.....then are we to conclude that somewhere in the middle
possibly is the truth? ]]]] everytime.

... I must of misunderstood myself .. please .. carry on

[DaemonCantor]

Well with all of this to the side. the fact that the systems require more power to operate correctly has been established in my humble opinion and then I started on the last point of endurance of the Power System and to that now I will point out some major facts of how to get more than 20mins of power. It has to do with the 50% to 70% efficiency thing which is that yes the PSU is more effective at 70% than at any other level but also will last longer due to Capacitor Loading. If you look at some of the better PSU calculators the ask about Load Rating, like: http://www.thermaltake.outervision.com/, now Thermaltake suggest 90% because it will burnout faster and you'll end up buying a new one with in a year but if you adjust it down to 70% then it will take 2 to 3 years for those BIG Capacitors to burn up. and what they do is stabilize the current passing through the Primary Stage as well as stop a bad back feed that could damage any and all equipment connected. A Switching PSU works in two to three stages, Primary that converts 120v 60hrz or what ever comes out of the wall in Europe to 35v DC through a Transformer with Filter Capacitors(the BIG ones) to stage Two which then breaks it into 3v, 5v, and 12v through Voltage Regulators(2 to 3 Depending on type) these are also called RAILS but not the RAILS your thinking of yet. Also in Stage two is filtering array of Capacitors. Rail 1 is your 3v line which is what the Second Voltage Regulator provides and is separate from the end Output RAILS and also requires more regulation. Next is Rail 2 which is your 12v Rail and it's what is divided into your 5v Rail as well through a simple Transistor Pair with Capacitor Filtering again. This rail is what most PSU use whether Single or Multiple RAIL. Next is you Rail 3 or Auxiliary Rail and that is present for additional Over Current power. Now on some of the more Expensive PSU's they have a third Stage which is the PWM Circuit and basically what this does is monitor the Output and adjust the Second and Third Rails as needed also in these more expensive PSU's are better Filtering, MOV's for Surge Protection, Better Fan and Temperature Control, More Voltage Regulators for additional Amperage as well as better components. This also doesn't constitute that more cost is better because some of the middle priced PSU's are really better than the Most expensive but it does say that the more power in the rating the better and longer it's going to last you.

There is a site that really goes into depth on the subject to the point that they tear the PSU's apart and examine the components and they are at: http://www.hardwaresecrets.com/. They not only examine PSU but all kinds of other parts as well heck they even have a review on Thermal Paste where they have even tried Lipstick and found that it works pretty good but Chocolate didn't work at all...Go look I've got time and there is a wealth of Info there ripe for the picking.

[XZEMi]

In my opinion the best power supply i've ever used to date is quite plain. Its the Antec EA650. Compared to Corsair and Seasonic this power supply remained cool to the touch under all loads. It was perfect for my mini atx case because its fan constantly evacuated heat from the case. I regret my switching it out for a more touted gold rated modular power supply. The new one would leave its fan off until it reached a certain temperature which caused the system to run warm overall. Now the Antec EA650 has nearly doubled in price. On the flip side of things I sold mine used on ebay for the price I paid new.

[Zka17]

DaemonCantor, it's interesting that you linked the Thermaltake's psu calculator, I was looking for it while we were discussing here (I knew that it's from a big company, just could not remember which one) :D I used that every time when i was building a new system and tried to decide on the psu.

Now, it would be interesting to put those parameters you gave us (AMD Dozer X6, HD 5870, etc) and see what wattage would result... Just to see how it fits to XZEMi's original 850W suggestion...

[Zka17]

XZEMi, based on "Compared to Corsair and Seasonic this power supply remained cool to the touch under all loads. It was perfect for my mini atx case because its fan constantly evacuated heat from the case." - let me guess: your mini atx case was one with a top-mounted psu. Otherwise I could not understand how any psu can get hot to the touch...

With the top-mounted psus which draw air from inside the case is one major problem: they are sucking in the naturally rising hot air produced by cpu, vrm, north bridge, graphic cards, etc. That is the reason why most of the manufacturers switched by now to bottom-mounted psu designs. If the psu is placed on the bottom, it means that is supplied with the coolest air we can find in a tower case - this in case if the psu sucks air from inside. But, most manufacturers today went even further and they are designing their cases with separate thermal zones - the psu draws air from outside (through bottom vent hole often equipped with filter) and exhausts outside. This way the psu is in the coolest place and won't contribute anyhow to the system's overall temperatures.

In conclusion, when designing a new built, it is very important to clarify the placement of the psu - and choose your psu accordingly.

[DaemonCantor]

Very True, in the old days when components supposedly didn't get as warn as they do now the PSU was mounted in the top so that the thing could stay warm enough to work. Have you ever looked at Thermal Diagrams for electronic Components, They show not only what temps the Item is working at when it blows but also what temps it works the best at and how much Ambient Air Temp changes the performance. I'm not telling everyone to become Electronic Engineers but just like most things a little info and knowledge will take you far. Back on track, Yes temperature is important to a point. and you have to take into effect Temp from the Components, Ambient Air Temp and also Load Temp all three of these make up what you feel. I've see components that were so hot that they would burn you but the core temps were with in normal ranges and there was no problem at all. It really all comes down to is don't Assume it's too hot. Most equipment today are created for the 45c to 70c ranges which do the conversion if your American 113f to 158f ...Sorry but that's as hot as Phoenix, AZ on a July 4th Holiday! and I've had some systems that ran Normal but scary as hell at 90c+ 194f that's just below Boiling Water and if you think that's hot then why is a Kray CPU submerged in Liquid? because the things normal Core Temp is 165c or 329f.

So if you think that PSU is too hot to the touch but it's Cooling Apparatus isn't running, then it's not too hot yet but yes it maybe too hot for the other components. Work on a better Thermal Environment first. IE better fan placement, better airflow, less obstructions in the cooling loop and proper Case Pressurization are all ways to not only keep equipment running longer but also needed to keep proper TEMPERATURES for Optimal efficiency of your equipment.

Zka17 I used that Calculator last night and it told me I needed a 980watt PSU for my system but you only need a 700watt for a Core i7 9360???? Same everything else Go Figure!

[Zka17]

"So if you think that PSU is too hot to the touch but it's Cooling Apparatus isn't running, then it's not too hot yet but yes it maybe too hot for the other components. Work on a better Thermal Environment first. IE better fan placement, better airflow, less obstructions in the cooling loop and proper Case Pressurization are all ways to not only keep equipment running longer but also needed to keep proper TEMPERATURES for Optimal efficiency of your equipment." - 100% agree! Maybe we should discuss how these above things can be acquired...

DaemonCantor, I'm sending a PM to you regarding further questions with the psu calculator - we may get to deep in this subject here, maybe others would discuss different things too...

Update: Forget something...

Also, I think, it's time to clarify one more thing! It is important to note what wattage we are posting here. I mean, some people are posting values from a psu calculator, others may share values given real time by a dedicated device - it may not be the same!!!

Just an example: my system's (mentioned on post #4) calculated wattage is 590W while I'm measuring peak values of about 450W - showed by the ups's built in system. Now, which is true?!

[DaemonCantor]

Ok in the PM you requested this and I just finish going back and doing Screen Captures.
820582068207

Wow!, Holy Sh1t, Unbelievable! But true!

[Zka17]

OK, then here is my calculation mentioned in my previous post:

8208

I know that these two are different systems, but there is just a slight difference between the cpus - 8W. Got curious from where is this big difference (again, I realized the two different systems - but still...). I replaced the graphic card - went up from 590W to 600W. Still doesn't match... Then i observed the 10 USB devices and 2 FireWire ones - recommendation went up to 641W (however, you should have mentioned this - who is doing stress-testing with so many things attached?!). Would be the Intel vs AMD - let's see: still 641W... And there is the front bay card reader - 651W... OK, I'm getting lost - will start over!

Man, this is odd! What I'm missing?! - tried to put your system's parameters, but getting different result...

8209

[xeromist]

The calculator is a good talking point but I wouldn't rely on it completely. In some cases it's going to go way overboard and in others it will fall short. I put in my old c2d system with tri sli and it's recommendation using "recommended" settings is a 604W PSU. I saw that system peak at 700W at the wall. In other cases you guys are posting smaller systems with bigger estimates than I've seen people use 24/7. Since we don't know how they got all of those numbers it seems hit or miss whether it will be accurate.

[Zka17]

That's what I'm saying! Whenever we are posting some wattage value, we should automatically mention if it's an estimate or a real/measured value. With the real/measured values we can not really argue... Then we can discuss how to estimate values - and here may be helpful if people would start posting the estimate values of their system together with the real values. After a while we could get a picture how these estimates are working...

[Kipper]

I didn't see anyone discussing AMPs so far.

I have always added up the draw of my components and then make sure the 12V rail is more than sufficient for the components I am using and a little room for upgrades down the line.

For all the PSU reviews I have done over the years for most of the big boys; TT, Corsair, Seasonic, Silverstone, Enermax and most of the rest of the big boys I would load up the test bench with some power hungry components and while stressing the system with a nice OC and hammering it with Prime and furmark and then monitoring the 3, 5, and 12v rails.

Haven't done in PSU reviews for a year or so now but still use my tried and true testing which can be done with an inexpensive multimeter.

Here are links to a couple nice units I reviewed last year.

High Power Plus Gold 1200W (http://pureoverclock.com/review.php?id=1262)

Seasonic X-series 850W (http://pureoverclock.com/review.php?id=1163)

[Zka17]

Wow, Kipper, nice power supplies you reviewed there! Somehow I never came across those... but I will keep them in mind! :cool:

"I didn't see anyone discussing AMPs so far." - you're right, we didn't get there yet... From my part, the reason is that I don't feel 100% sure if I've got the idea of single vs multiple rails...

Could somebody elaborate more on this, please?

[DaemonCantor]

Zka17, did you read the post where I described how a PSU works? If not take the time and read it.

The Second Stage there is where your Power RAILS come out and what they do is instead of one Voltage Regulator(Single RAIL), they use up to four cheaper ones(Four RAILS) and divide the current across all of them. An AMP is still an AMP but now instead of like 70amps coming from one RAIL you now have that 70amps divided between up to 4 RAILS or 70/4=17.5amps each which gives Voltage times Amperage = Watts or 12v*17.5amps=210watts per RAIL on a 4 RAIL system but now you also have to take into consideration of where the 5v is coming from and that's the 12v RAILS so now you loos that extra 10watts per RAIL to the 5v line and end up with 200watts per RAIL. Your 3v is still seperate so that's not even a consideration at this point.

I hope this explanation is easy enough to understand.

[XZEMi]

XZEMi, based on "Compared to Corsair and Seasonic this power supply remained cool to the touch under all loads. It was perfect for my mini atx case because its fan constantly evacuated heat from the case." - let me guess: your mini atx case was one with a top-mounted psu. Otherwise I could not understand how any psu can get hot to the touch...

With the top-mounted psus which draw air from inside the case is one major problem: they are sucking in the naturally rising hot air produced by cpu, vrm, north bridge, graphic cards, etc. That is the reason why most of the manufacturers switched by now to bottom-mounted psu designs. If the psu is placed on the bottom, it means that is supplied with the coolest air we can find in a tower case - this in case if the psu sucks air from inside. But, most manufacturers today went even further and they are designing their cases with separate thermal zones - the psu draws air from outside (through bottom vent hole often equipped with filter) and exhausts outside. This way the psu is in the coolest place and won't contribute anyhow to the system's overall temperatures.

In conclusion, when designing a new built, it is very important to clarify the placement of the psu - and choose your psu accordingly.

Side mounted over video card.

http://www.amazon.com/Lian-Li-Tower-Aluminum-Microatx-Retail/dp/B0057BSGJ4

Lian Li PC-V354

[chrsplmr]

Kipper .. I got to say .. boy when I am wrong it is a doozy ... This thread is awesome.
Thank You All... ooops. (Sorry it smelled funny and setOff my FlapOmeter .. I was wrong.)

... The only thing I enjoy more about this forum than helping someone is all the opportunity to learn.
Look Ma, Im learning .. No hands.

.. sorry to interrupt .. please, continue ...

[Zka17]

Nice little case, XZEMi! One that cry after modding right as you got it...

One of the first hits I google it was this review: http://xsreviews.co.uk/reviews/cases/lian-li-pc-v354/

Even there is mentioned what sticks to my eyes: the PSU is drawing air from the VGA. Now I understand why are you concerned about the PSU’s temperature! I didn’t found this a great idea... In some circumstances the VGA may be the hottest component in your system, cooling it with the PSU... – well, that PSU wont last too long (and lucky if the PSU is dying only by himself and is not taking some other components with too).

So, my idea is to invert the PSU with it’s intake toward the side panel. Then cut a big hole on the side panel accordingly with the PSU’s intake. I suggest you to put some dust filter over it – then you will stop worry about PSU’s temperature forever! :cool:

[Zka17]

DaemonCantor, I have to confess that I didn't get 100% sure how the PSU works from your previous post (#23)... - since then, however, I did my homework and read a lot about, and now with your second post (#35) starts to get clearer and clearer! Thank you for leading me in this process! BTW, you didn't comment on my post #30 - I'm extremely curious how you would explain the discrepancies...

Just to conclude for myself (please correct me if something is still wrong): Rails are practically voltage regulators. Regarding the output, there are at least 3 rails/voltage regulators - one for each of 12V, 5V, 3V. Number of rails/voltage regulators depends on the quality of components used - cheaper ones has more, performant ones has less. The amperage on each rail is determined by the manufacturer/way how the transformers are designed. Is this right until this point?

Now let's take two supposedly high end PSUs: Corsair AX1200 and Silverstone ST1500 (choosed these because I own them, and they are perfect for the reason of this post - yes, I know, they have different efficiency ratings). I prepared a table with their voltages, amperages and wattages:

8265

Now, my question is: For an average system builder, which design suppose to be better - single or multiple 12V rails? In case of two PSUs with the same efficiency ratings the single rail would only mean higher quality? Would there be arguments for using multi-rail ones?

What I see from the Silverstone's specs: although it has eight 12V rails each rated at 25A, the max combined load can be only 110A (instead of 8x25=200A) - why?

[DaemonCantor]

Zka17, Your answer to post #30 was done by xeromist but let me go a little further in I don't hold stock to the Calculators because on many occasions I've used them multiple time with the same exact info only to get scores all over the place plus they differ from site to site so how can you be sure if 981watts is correct when the next person gets 575watts and then you go back and get 692watts and then you go to NewEgg and get 1192watts... I see no real value except for comedy.... Really think about it, how in the hell could a system that takes 350watts just to fire up with out a Video Card need only a 550watt PSU with a card that requires 180watts from the system bus. That only leaves 20watts for when the system goes in to High Performance like playing a game...Wow I can see a lot of people buying PSU's every time they play Crysis! Now remember the link I posted on the power of the 5870 that same system would need a 350watt + 354watts = 704watts minimum with out any room for possible extra power but you still have to add that into it and like I was saying you need a minimum of 30% for reserves which in this case is 212watts so now were at 704w + 212w = 916watts. Like Kipper stated basically 'Do the Math!'.

Ok your getting a clearer idea but on a Single RAIL design it doesn't have three RAILS(12v, 5v, 3v) it has two RAILS a 3v, and the 5v and 12v are one in the same RAIL.
On that Silverstone PSU 200a - 40a(+5v) = 160a - 63a(-12v & +5vsb) = 124a - 14a(reserve) = 110a ... Tey are giving the Power output off the Primary Stage 'Calculated' instead of the Secondary(Output)stage and a easy way for them to cut Cost in Production because they don't have to give a single bit of extra power like Higher Quality Units... Like I stated Higher Price Doesn't mean Higher Quality!

[Zka17]

As I’m getting older learning new things is getting harder... Man, how many times I clarified for myself that the 5V and 12V are in the same rail! Well, I really appreciate this thread – by the end will get all this things correctly... hopefully... :D

Regarding my post #30, xeromist didn’t answer my question: How I’m getting different wattage value using the same PSU calculator with the same components? I was asking you to check if I didn’t miss anything filling up that form.

You’ve got 981W versus 648W I’ve got as result. That’s serious difference, DaemonCantor! How that happened?! Since then every day, multiple times checking it but every time gives me the same result: 648W. You’ve mentioned the Newegg’s PSU calculator, with the same hardware – that’s much simplier (asking for less info, offering less choises), I choosed CPU: AMD Phenom X4, high end desktop motherboard, one HD 5870, two sticks of 4GB DDR3, two blurays and three 5400rpm 3.5” HDDs. Guess what? “Our recommended PSU Wattage: 624W”! It seems pretty consistent with the Thermaltake’s one...(considering that is asking less things, so giving lower value). That’s far less than 1192W you were talking about...

I’m really trying to understand how you, DaemonCantor, came up with those high wattages! I could accept that different calculators may show different results (that’s why you should rely on the values obtained on a wattage meter at the wall), but the same calculator with the same parameters is giving the SAME results...

“Now remember the link I posted on the power of the 5870 that same system would need a 350watt + 354watts = 704watts minimum with out any room for possible extra power but you still have to add that into it and like I was saying you need a minimum of 30% for reserves which in this case is 212watts so now were at 704w + 212w = 916watts.” – are you reffering to post #12 (and this link: http://www.tomshardware.com/reviews/radeon-hd-5870,2422-20.html)? Just because the wattage value of 354W given there for a single HD5870 is the whole system’s consumption, not the graphic card’s only! So from where did you get the extra 350W to end up with 704W?!

“Like Kipper stated basically 'Do the Math!'.” – yeap, man, but if you’re using a formula, then explain each value you put there! :cool:

As I said, I’m really trying to understand these things...

[XZEMi]

Thinking i'll invest in another corsair cx430. You know back in 1999 the 436watt enermax whisper power supply was $120 and people said it was really more than you'd ever need. I tested that theory and used one to run an amd x4 550BE converted it to sata really it had no trouble running the system but it wasnt nearly as efficient as these newer power supplies. The CX 430 is excellent and can be had for under $25 at newegg on a good sale. Oh and just a little something I looked up for rewiring my power supply connectors. 829782988299

[xeromist]

I just wanted to comment on the single vs multi-rail bit. Some of the justifications given for multiple rails is that they provide some degree of isolation between components and that by splitting closer to the transformer you have less current traveling through many of the components so they can potentially last longer (given equal quality of components). Being multi-rail is not a direct indicator of quality, just a different approach to things. In the early days of the multi-rail fad the people utilizing it were doing it to produce cleaner and more stable power supplies. At some point the el cheapo manufacturers jumped on the band wagon because they realized they could use smaller & cheaper components while drawing on the good name of multi-rail established by their betters. Likewise there have been manufacturers using cheap components to produce single rail that might stand up to the current but with a nasty ripple and voltage swings barely within spec.

The drawback of multi-rail is that you have to properly allocate those rails whereas single rail is just plug & go. And if you have a device that draws less than the rail allocation this could mean some amount of power overhead being "trapped" in one of the rails and thus unusable elsewhere. Even with perfect allocation on your current build a side effect of this is should you move the PSU to a dramatically different build you might find that the rail division is no longer convenient.

All of that said, single or multi rail I am most concerned about the quality of the power produced. It doesn't matter how many rails it has, if it won't deliver clean power I won't buy it.

[Zka17]

Wow, xeromist, I never heard about "the drawback of multi-rail is that you have to properly allocate those rails whereas single rail is just plug & go" - it sounds serious though!

What exactly means to "properly allocate those rails"? Taking as example my Silverstone ST1500 with it's eight 12V rails...

[xeromist]

In the classic definition of multi-rail each rail is allocated a fixed division of power which cannot be used on other rails. Say a rail is allocated 15A but whatever is connected to it is only drawing 5A. There is another 10A of head room you aren't using. If another 15A rail is connected to something trying to draw 20A then you will hit overcurrent protection even though you still had power to spare elsewhere. In the case of an ST1500 this really shouldn't be a problem because each rail is rated to 25A and even high end cards don't pull more than that from a single connector. That's why such cards have 2 or more connectors.

Also, some "multi-rail" PSU's are a bit tricky because they are essentially combining rails as needed or otherwise trying to work around the issue of unequal distribution.

[Zka17]

So, based on these, every connector on the back of a PSU is meaning a separate rail?

In case of the ST1500 the 24 pin, 8 pin and 6 pin connectors are all meaning a rail? Or this one is "tricky" too?

Also, generally speaking, if you have a PSU with one PCI-E cable but the graphic card would require two - what is best to do? Split that PCI-E cable/connector - risking that you can ran into the over current protection. Or use some adapter cable from an other connector - which may not be designed for graphic cards (like other rail with lower amperage).

Thanks xeromist, I really feel that I'm getting closer to understand better this component of a pc!

[xeromist]

So, based on these, every connector on the back of a PSU is meaning a separate rail? Not necessarily. I have had multi-rail power supplies with two connectors on the same rail but each of those rails was separate from each other.


In case of the ST1500 the 24 pin, 8 pin and 6 pin connectors are all meaning a rail? Or this one is "tricky" too? To learn more about your PSU I would recommend Jonny's review. He generally does a pretty good job and he also discusses rail division on the ST1500
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=175


Also, generally speaking, if you have a PSU with one PCI-E cable but the graphic card would require two - what is best to do? Split that PCI-E cable/connector - risking that you can ran into the over current protection. Or use some adapter cable from an other connector - which may not be designed for graphic cards (like other rail with lower amperage). Ideally it's best to use a PSU with the correct connectors but if you have an older PSU with adequate power and a shortage of connectors you can use adapters. It's important to keep the specs of the PSU in mind however and not just throw some adapters on any old way. I've used splitters on 25A rails with cards that weren't overclocked and 4pin molex adapters on drive/accessory rails with only a few other devices. In both cases I knew I had the power available so I felt safe doing it.

[Zka17]

Thanks very much, xeromist - just finished reading Jonny's review I found since my last post. :D It really is a nice review!

[FR3D1]

Hi XZEMi since ya like an expert at psus can u help me choose a good psu?
I want a good, cheap, sli certifiled psu, save electric so which is the best value to choose? What brand and model?

[Zka17]

FR3D1, I bet you would be more satisfied with XZEMi's answer if you would mention what you need that "good psu" for... Man, how you expect anybody to give you a correct hint if you don't post your system's specs?! As you can see in this thread, there are a lot of discussions even in the case we know all components of a pc. So, go ahead and specify your hardware!

[FR3D1]

My spec is
Asus M5A97-EVO
AMD phenom ii x4 810
8G Kit 1600 ripjaws x
1x sdd, 1x 2tb hhd, 1x dvd drive
watercool ready
and aslo want a sli certifield psu cause might upgrade to GTX650

[Zka17]

OK, FR3D1, slowly but certainly getting there...

Now, would you share with us what graphic card are you using in this system? Or it's just a build plan and you are really waiting for release of GTX 650? I'm asking this, because the graphic card is one of the main power drawing component of the system - without knowing what you have, it's hard to pick up a PSU...

Also, observed in your other thread that you're intending to get one GTX 650. Are you aware that in order to have SLI, you need at least two graphic cards? Just saying... As I explained above, it does matter what type and how many graphic cards are in your system when you are looking for a PSU.

In your previous post in this tread (#49) you mentioned "save electric" among your expectation from the PSU. I feel, here you need some clarification... The PSU can be electric saver in only one way: by being highly efficient. Other than that, the electric consumption is determined by your other components - i.e. if your system draws let's say 500W, doesn't really matter if you're using a 600W or 1200W PSU, the consumption will be the same. Regarding the efficiency, there are several choices: 80 plus (80%), 80 plus bronze (82%), 80 plus silver (85%), 80 plus gold (87%), 80 plus platinum (90%). As you can see, there is a max 10% difference between the min (I don't even take in consideration no-name PSU's with efficiency lower than 80% - you should avoid them too) and max. However, in their price tag certainly is a bigger difference. So, you have to decide on this.

So, getting back to your initial question, it also would be helpful to know what for do you need this system? What type of applications will you run, gaming, simple working (internet browsing, MS Office) or more serious work (Adobe Photoshop, 3D rendering, video editing)? Are you planning to overclock?

As you can see, more input needed... Right now, without a graphic card (based on the components you listed) you are below 300W of power draw. Even if I take the initiative and say you would overclock and use two GTX 680s you would be around 600W... - with two GTX 650s certainly below this. So, give us more info and we can continue!

[FR3D1]

since we hav no spec about the gtx650 how about gt560ti( casue it similar) and would it need at least 800w psu for my system if i use two gtx560ti? i only use for gaming mainly.

[XZEMi]

since we hav no spec about the gtx650 how about gt560ti( casue it similar) and would it need at least 800w psu for my system if i use two gtx560ti? i only use for gaming mainly.

800 would be plenty. The GTX650 will be more efficient and draw less power than a 560ti or maybe even the gtx550. In either case 800 on the high end I wouldnt go any higher. At the expense of watts i'd just find a good deal on a 750 watt unit. Corsair, Seasonic, heck think even XFX, and Antec are making good power supplies these days. Corsair has a great 750watt professional modular silver rated power supply for about 130 if you shop around its a very nice unit.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139010

i've used one it was impressive.

[FR3D1]

but the bad thing is i liv in australia the only good shop i found is msy but it doesnt hav everything u can try take a look @ msy.com.au

[speed]

"For instance you dont want a seasonic gold modular power supply in a small form case because it will not always run its fan and evacuate the heat. You would be better off getting a cheaper supply that has a fan constantly running."

Anyone who would use their power supply as a case fan is not too smart imo. Drawing all the hot air in a case into the power supply that also makes heat is down right dumb.

[Zka17]

"Anyone who would use their power supply as a case fan is not too smart imo." - I agree with you, speed, just don't forget the case design! The older cases are designed with the PSU place on the top, exhausting. Or like XZEMi's case (post #36 in this thread). So, all depends on the case you're using and/or your willingness to do some modding... :cool: