Asus Z490 stuff

[GemueseMonster]

just to reiterate, not sure if this issue is known yet or not, this is the RTL/IO-L training inconsistency issue I'm seeing.

from boot to boot, with identical bios settings, sometimes RTL/IO-L of one channel drops to some sort of fallback at ~74/~14, while the other trains properly at ~62/~3 in this case. all screenshots are with identical bios settings, apart from the last with one channels IO latency offset changed from 25 to 23, to clarify that it's not a capability issue of the memory modules.

to get around that, I have to keep rebooting and checking the values in BIOS until they are proper (both channels at ~62/3, then enable MRC fast boot to "conserve" the trained values and boot into windows. needless to say this is kind of an ugly solution.

so is this expected, or a glitch in bios that Asus can fix, or a glitch in IMC microcode that Intel needs to fix?
would love to get some feedback, thank you.

[bscool]

just to reiterate, not sure if this issue is known yet or not, this is the RTL/IO-L training inconsistency issue I'm seeing.

from boot to boot, with identical bios settings, sometimes RTL/IO-L of one channel drops to some sort of fallback at ~74/~14, while the other trains properly at ~62/~3 in this case. all screenshots are with identical bios settings, apart from the last with one channels IO latency offset changed from 25 to 23, to clarify that it's not a capability issue of the memory modules.

to get around that, I have to keep rebooting and checking the values in BIOS until they are proper (both channels at ~62/3, then enable MRC fast boot to "conserve" the trained values and boot into windows. needless to say this is kind of an ugly solution.

so is this expected, or a glitch in bios that Asus can fix, or a glitch in IMC microcode that Intel needs to fix?
would love to get some feedback, thank you.

As far as I know that is normal if your pushing the memory or it is on the edge of stability. That is why many set all the timing manual so they stay set. Every Asus board I have(z390 Apex/Hero, z490 Apex) does the same when pushing the memory so I set everything manually.

To test what I am saying put the memory down to say 3600-4133(depending on board and RAM) and it will train correctly every time. I saw in another post of yours you mentioned training above 4500, that is starting to pushing things even on the Apex and will probably require manual settings if you want to ensure the timings stick after every boot.

Just because the Apex has QVL to 4800-5000 many will still be limited to much less because of RAM or the CPU IMC. On overclock.net you will see most run the Apex from 4400-4700 and these guys that have bought multiple kit of memory and some multiple CPU to bin for the best ones. https://www.overclock.net/forum/5-in...l#post28553378

As far as i can tell and from what I have seen from others posting RAM OCs I don't think the z490 RAM OC improved much over z390 and in some ways went backwards. I have a z390 Hero also and from what I can see it will give as good or better performance(lower latency) and clock higher(on RAM OC) than most of the new Z490 4 dimm boards. It looks like many struggle to get 4 dimm 4133 17-17-17 stable.

[GemueseMonster]

As far as I know that is normal if your pushing the memory or it is on the edge of stability. That is why many set all the timing manual so they stay set. Every Asus board I have(z390 Apex/Hero, z490 Apex) does the same when pushing the memory so I set everything manually.

To test what I am saying put the memory down to say 3600-4133(depending on board and RAM) and it will train correctly every time. I saw in another post of yours you mentioned training above 4500, that is starting to pushing things even on the Apex and will probably require manual settings if you want to ensure the timings stick after every boot.

Just because the Apex has QVL to 4800-5000 many will still be limited to much less because of RAM or the CPU IMC. On overclock.net you will see most run the Apex from 4400-4700 and these guys that have bought multiple kit of memory and some multiple CPU to bin for the best ones. https://www.overclock.net/forum/5-in...l#post28553378

As far as i can tell and from what I have seen from others posting RAM OCs I don't think the z490 RAM OC improved much over z390 and in some ways went backwards. I have a z390 Hero also and from what I can see it will give as good or better performance(lower latency) and clock higher(on RAM OC) than most of the new Z490 4 dimm boards. It looks like many struggle to get 4 dimm 4133 17-17-17 stable.

thank you for your input.

unfortunately when I set the values manually, and even back off by one to be safe, like 62-4 and 63-4, training does not work at all (post code 55)
so using io latency offset is the only way to get IO-L's with good performance trained at those sorts of clocks atm

also I have noticed that 4266 is some sort of cut off. below 4266 the io latency offset is applied positively, meaning lower offset = lower RTLs/IO-Ls. over 4266 the io latency offset is applied negatively, meaning lower offset = higher RTLs/IO-Ls and higher offset = lower RTLs/IO-Ls.

if I had to guess, this is some kind of historically grown duct tape approach in the IMCs microcode for supporting > 4266 that worked fine with < 8 cores, but now with increased ring length of 10 cores becomes dodgy.

an IOL difference of 1 seems to equal about 0.1ns of latency. so both channels running at default IOL 14, as opposed to properly trained 3 e.g., is a memory latency penalty of 14-3 * 2 * 0.1ns = 1.8 ns ~ 5 %.

probably not a big deal for most users, but significant enough to be addressed imho.

[bscool]

thank you for your input.

unfortunately when I set the values manually, and even back off by one to be safe, like 62-4 and 63-4, training does not work at all (post code 55)
so using io latency offset is the only way to get IO-L's with good performance trained at those sorts of clocks atm

also I have noticed that 4266 is some sort of cut off. below 4266 the io latency offset is applied positively, meaning lower offset = lower RTLs/IO-Ls. over 4266 the io latency offset is applied negatively, meaning lower offset = higher RTLs/IO-Ls and higher offset = lower RTLs/IO-Ls.

if I had to guess, this is some kind of historically grown duct tape approach in the IMCs microcode for supporting > 4266 that worked fine with < 8 cores, but now with increased ring length of 10 cores becomes dodgy.

an IOL difference of 1 seems to equal about 0.1ns of latency. so both channels running at default IOL 14, as opposed to properly trained 3 e.g., is a memory latency penalty of 14-3 * 2 * 0.1ns = 1.8 ns ~ 5 %.

probably not a big deal for most users, but significant enough to be addressed imho.

What kind of latency are you getting? I am getting and see other in 34-35ns range using Aida64 to test.

[GemueseMonster]

What kind of latency are you getting? I am getting and see other in 34-35ns range using Aida64 to test.

granted there is some run-to-run variance with aida64 memory benchmark, but this proves my point. both channels trained vs. one channel dropped to fallback IO-L 14, ~ 0.1ns latency penalty per dropped IO-L

and to clarify, exact same bios settings, just a reboot between these

[Lotzi]

Hey Peter

Any new Bios for Z490 E Gaming since 0704?

[BloodBaron]

Hey Peter

Any new Bios for Z490 E Gaming since 0704?

I'm also waiting for a new bios for the Strix Z490-E, as i can't seem to get my XMP speeds on memory F4-4000C17Q-32GTZR (4000-17-17-17 @1.35v, tried a adding more voltage, loosening timings etc) and latency (~47.5ns) seems high compared to what other are posting.
I've also noticed that APCI.SYS is causing latencymon to say my system isn't suitable to realtime audio, which i think someone else had posted a few pages ago.

Should i jump up to the 0704 bios?

[bscool]

granted there is some run-to-run variance with aida64 memory benchmark, but this proves my point. both channels trained vs. one channel dropped to fallback IO-L 14, ~ 0.1ns latency penalty per dropped IO-L

and to clarify, exact same bios settings, just a reboot between these

It seems like your memory is not stable. I can set my IO-L and all the other settings manually and they boot and work. The only time they wont is when it is on the edge of stability then they might work one boot and not another.

Have you ran any stress test or just bench marks when it does train correct?

I haven't seen anyone else posting about IO-L not working on the Z490 Apex or have you and can you post links I would like to read more about it?

Also why do you set IO offset to 25 instead of 21? I find it harder to boot 25 and if set to 21 and then set the other timings down it gives the same performance when I compared the two methods. Or is there something else it effects?

Here you can see he has IO and every thing manually and it works.

https://youtu.be/jey8x1JB6yo?t=4913

[GemueseMonster]

It seems like your memory is not stable. I can set my IO-L and all the other settings manually and they boot and work. The only time they wont is when it is on the edge of stability then they might work one boot and not another.

Have you ran any stress test or just bench marks when it does train correct?

I haven't seen anyone else posting about IO-L not working on the Z490 Apex or have you and can you post links I would like to read more about it?

Also why do you set IO offset to 25 instead of 21? I find it harder to boot 25 and if set to 21 and then set the other timings down it gives the same performance when I compared the two methods. Or is there something else it effects?

Here you can see he has IO and every thing manually and it works.

https://youtu.be/jey8x1JB6yo?t=4913

it's not instability. I can lower clock by 300 MHz and behavior is still the same. I have also tried different memory kits and different cpus, so my board is defective?

Why offset 25? Because it results in IOLs/RTLs 4 lower than 21... What "other timings" do you mean that give you the same performance?

He's entering 7 in the video. So are IOLs lower than 7 not supported on the apex? I dont get it.

[Betroz]

So are IOLs lower than 7 not supported on the apex? I dont get it.

With DDR4 4400 and above, IOL of 7 (or higher) is needed. Check out my settings as an example :