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Helios
01-06-2012, 11:47 AM
Hey, i bought and just recieved my g53sx yesterday, everything seems good hardware wise, and today ill clean the drive and make a clean install.

I only have one question, my power brick, which is humongous, is making a buzz, two buzzes to be exact a low hum buzz and a higher mid hum buzz.

My last laptops brick, started buzzing and about a month later it turned into a highpitched wine and gave up.
So my question is does anyone else have this buzz, is it normal with a powerbrick of such high watttage, or should i request an rma or contact asus or what?

Thanks in advance

another somewhat related question, am i correct to assume that at 12v via inverter, the laptop will consume 20amps/hr so an 85 ah deep cycle battery would give me about 2 hours of time before i have to start recharging it

dstrakele
01-06-2012, 03:06 PM
The power brick that came with my G74SX-A1 is silent whether it is charging or not. Like you, I would be very suspicious of the noises you hear coming from yours.

Where did you buy your G53SX? I'd would return to the retailer and examine the same power brick in operation. Ask the retailer if they will exchange your power brick for a new unit. If they don't wish to do it, you could see how they would reply if you said "OK, we'll I'm going to return the laptop for a refund." Don't let them talk you into an RMA to ASUS for replacement under warranty. That would make it YOUR problem. Let ASUS deal with it.

I think 2 hours is a good estimate of your battery time. I find the Windows battery icon is reasonable in it's estimate of battery life, although I have seen cases reported where it was off as much as 15%.

Helios
01-06-2012, 08:45 PM
newegg, and the battery seems pretty good, as i used it for about 40 mins and it went from 100% to 73% battery saver mode and light webbrowsing with pandora in the bg

and i can only hear the buzz when i put it on my ear, when on an ac plug, and when i put it on an inverter its a bit noisier, maybe the inverter is causing extra noise in the electrical current

dstrakele
01-06-2012, 08:55 PM
You could take the power supply to an electrical shop to have them test it.

You may also wish to email Newegg about it and save the resulting correspondence. That would give you something in writing that you reported the issue at this time. If the power supply should fail beyond their return date, you'd be able to verify you reported a possible problem with it earlier. That may help get you a replacement without charge.

Helios
01-06-2012, 09:41 PM
thanks, i wouldnt have thought of doing that,

i have the 1 year accidental coverage with asus, but this makes me want to spring for the other warranty i think its 99 for 2 year replacement/repair

is it worth it, and just finished talking with newegg, they basically said contact asus and if they say its defective they will issue an rma....

dstrakele
01-06-2012, 10:59 PM
thanks, i wouldnt have thought of doing that,

i have the 1 year accidental coverage with asus, but this makes me want to spring for the other warranty i think its 99 for 2 year replacement/repair

is it worth it, and just finished talking with newegg, they basically said contact asus and if they say its defective they will issue an rma....

It's in Newegg's interest to get you to contact ASUS and RMA because then it's YOUR problem and not theirs. If you want to play hard ball, you could say "OK - This power supply is defective. If you won't replace it, I'll just return the whole laptop to you for a refund." I'm not sure what their policy is, and a restocking fee may be involved if the part is not defective. But there's a possibility you might make 'em sweat since electronics retail was not as strong as anticipated this Christmas season.

It's your decision though, don't do it just because I said it.

fostert
01-07-2012, 04:40 AM
another somewhat related question, am i correct to assume that at 12v via inverter, the laptop will consume 20amps/hr so an 85 ah deep cycle battery would give me about 2 hours of time before i have to start recharging it

Your laptop consumes a certain wattage of power, which is energy per unit time, by pulling a certain amount of amps from a specified voltage (in this case, that of your power brick). This wattage must therefore be supplied by your inverter, which itself is pulling current from your deep cycle battery (I assume some sort of RV battery?) at 12 volts. The G53 uses a 150W supply, so that means at maximum load (when your notebook is drawing ~150 W) your current draw from the battery will be ~12 amps. Therefore an 85 A-h battery will supply this for ~7 hours. You won't be using 150W all the time, so your battery life with a deep cycle 12 volter will be much longer.

Helios
01-08-2012, 08:51 PM
thanks for your help, i'm looking into confirming my brick is defective to return it,

and as to forstet, thanks for the explanation

fostert
01-09-2012, 02:09 AM
No problem. BTW, the above assumes 100% efficiency of your inverter at converting DC to AC; more realistic efficiencies are 50% (for low draw) to 90% for full rated load of your inverter, so in reality your actual battery life would be cut by up to 1/2 (at low load) due to loss.

Helios
01-09-2012, 08:49 AM
i knew that using an inverter wouldnt be an efficient way of using the battery but didnt imagine a possible loss of half the capacity.

ok so correct me if i'm wrong what youre saying in order to get the most of the battery im going to have to get an inverter as closest as possible to the wattage i need in order to use the full capacity of the inverter and the energy isnt dissipated as heat.

i know the specs state the laptop using 150w, but the adaptor is rated at 100-240~2.0A wouldnt that make it a 200watt load? i have a 200w continuous/400peak inverter, right now

i still havent made any purchases, and i was in between buying a marine/deepcycle battery and a charger to charge at home, or a small generator, they both would cost about the same, i ofcourse was leaning towards the battery, for silent use and less stuff to carry around


the generator is still an option but seems like overkill and very unefficient, as the smallest ones i could find were 1000 watts, but it is still a choice

i would use this setup daily, as i operate outdoors, for almost 12 hours at a time, the battery wouldnt have to last that long but i would like to have it charging during the day, and ready to go that night. i was contemplating setting up a dual isolated battery setup in my vehicle in order to charge it but i learned that i could endup damaging the alternator, or the battery in attempts to charge it, and doubt it would be charged as i only have abour 40 mins of highway time daily

hehe sorry for the wall of text XD i just like to make informed decisions

fostert
01-10-2012, 04:04 AM
I think the inverter you have will do fine. It looks really well matched to the peak load of your G53, which would be 150W. The reason the adaptor is rated higher at 200 W is reflecting its efficiency as a power supply: i.e. when your laptop is pulling 150W DC from the brick, the brick is pulling 200W AC from the wall: 150/200=75% efficiency which is quite normal. The efficiency will be higher (80% or more) when you're drawing closer to 50% of the brick's capacity (75W).
Your inverter is rated for 200W continuous, which is what it will pull from the battery when your laptop is working at full load. And if you're playing games or some other reasonably intensive activity lots, then the inverter will still be operating at its higher end of efficiency (70-80%). Again, sounds like a good setup.

I would think your setup would still last for ~12 hours at a time if you're not continuously running at full speed. A decent load would be 75W (50% continuous load on CPU & GPU etc), so you could expect to be drawing about 6 amps from the brick. 85Ah would nominally give you 12 hours at this level, but factoring in the efficiency of the AC-to-DC conversion by the brick (say 80%) and the DC-to-AC conversion by the inverter (say also 80%), 0.8*0.8*12=~7.7 hours. Again, thats at 50% continuous load: I would think that you wouldn't be running it that hard all night, and that there would be long periods of near idle, so 12 hours is a good estimate.

Helios
01-10-2012, 07:26 AM
thanks again, youve been a great help at settling my doubts, and yea maybe 2-4 hours would be at full load with gaming, and maybe another 3 just staring at ide's or web browsing, when i idle the laptop or just leave pandora up, i usually turn off the lcd, to conserve battery

now to scavenge my friends&relatives garages in search of an old battery, to avoid the core charge, lol every penny counts XD