Help! System hangs/freezes when overclocked

[Thireus]

Hi,

I recently got the following configuration setup:

CPU - i9-7980XE
RAM - 8x16GB = 128GB of RAM - G.Skill F4-3200C14Q2-128GTZS (https://www.gskill.com/en/product/f4-3200c14q2-128gtzsw)
MOTHERBOARD - ASUS Rog Rampage VI Extreme
BIOS 1004

I am currently trying to diagnose system freezes/hangs/crash that seems to occur after several hours of uptime (tested on Windows 10 or other OS). I am not able to diagnose exactly where the issue is coming from, but from the BSOD dumps it appears this is memory related. I've tried both the CPU settings set to "Auto" and to Manually set a Multiplier and Core Voltage in the BIOS, but still the same issue occurs. The only thing I can think of now is XMP.

I am trying to narrow down where the issue could be coming from, so any suggestions would be greatly appreciated.

After running 24h of memtest86+ 5.0.1 (which did one and a half pass), with XMP enabled, no issues were detected.
After running 5-13 hours of Prime95 the system would eventually freeze or crash at some point, and the BSOD dumps are of type MEMORY_CORRUPTION_LARGE and MEMORY_CORRUPTION_ONE_BIT_LARGE.

The BSOD information states that the issue is memory-related, which makes me think that the Voltage set by default when XMP is enabled is incorrect. When enabling XMP in the BIOS, it sets the Voltage to 1.350V which is indeed the correct value that the RAM is supposed to get at 3200Mhz. However the following happens:



As you can see there are two issues:

1. The Voltage reading is incorrect and too high: it reads 1.360V instead of 1.350 --> Why? Is this normal?
2. The second DRAM Voltage value flickers between 1.344V and 1.360V --> Any clue about what's happening there?

I have tried to swap all the RAM from CHC&CHD DIMM slots to CHA&CHB DIMM slots, but the same happens, the CHC&CHD DRAM Voltage fluctuates... Could it be related to my issue?

As for now, I have decided to bring the XMP settings back to disabled and run Prime95 again for the next 24h (unless the system freezes again) to double check that it indeed comes from the XMP settings and no anything else. I will report back here.

If anyone has any idea about what I should check/set to resolve the issue, I would really appreciate it. Been trying to resolve this for a week now. 😞

Thank you!

[Raja]

Thireus wrote:
I finally have the answer to the freezing issues I've been having! And I’m quite confident this is an issue with the Asus Rampage VI Extreme motherboard or maybe with the BIOS!

On the Asus Rampage VI Extreme, enabling both XMP and Core C-State will cause the system to freeze or crash after a few hours. When on stock settings, these two options are incompatible, at least on BIOS 1004. Therefore, I would like to request Asus to have a look at this technical issue, which clearly appears to me to be a board instability.

The following BIOS setting is responsible for the system freezes when XMP is enabled:

Autonomous Core C-State [Enabled]

All other settings (except XMP and the above) should be on stock!

To reproduce the issue and cause system freezes that occur as soon as possible after system boot on Windows 10, one can run Prime95 v26.6 with the following Custom Torture Test settings:

Min FFT: 8
Max FFTP: 4096
Run FFTs in-place: Checked
Time to run each FFT size (in minutes): 1

Also, running 2 instances of memtest from HCI Design: http://hcidesign.com/memtest/, with the maximum available memory might help trigger the freeze when running Prime95 in parallel. Although, when freezes occur memtest should not find any memory errors! (unless you have bad memory, which is not my case as I've already tested my memory)

Anyway, with the above C-State enabled, XMP enabled, and everything else on stock, the system should freeze after several hours of stress test, which should freezes after a maximum of 2h elapsed on the stress test which should be equivalent to 230% of memtest coverage. However, I have noticed that with other options enabled, such as the ones I mention in my first post, these freezzes can instead be system crashes (BSOD) in which case the Windows minidump after BSOD will be mentioned that this is memory related, sometimes it will be MEMORY_CORRUPTION_LARGE, sometimes MEMORY_CORRUPTION_ONE_BIT_LARGE. Crashes/Freezes can also occur much sooner too! If you wish to test your system stability with XMP and C-States enabled, I would recommend to please make sure to have everything on stock settings before enabling both XMP and Autonomous Core C-State only in the BIOS, that way you’ll only get system freezes!

As for now, I will leave "Autonomous Core C-State" on Auto (which I assume is in reality disabled). I will also write Asus an email about the issue, and hopefully their technical team will be able to fix this bug in a future BIOS release.

I was also curious to know if others had similar issues and decided to Google about it, and I found people who reported in the past that enabling C-States was incompatible with XMP and would cause their system to crash after several hours, which happens to be the issue I have with the Rog Rampage VI Extreme: https://vip.asus.com/forum/view.aspx?board_id=1&model=P7P55D+LE&id=20150520045828228&page=1&SLanguag...

Does anyone understand why, when enabling C-States on my config and with XMP enabled, the system would freeze after several hours? (When XMP is disabled C-States are perfectly working fine)

---------

@Raja, do you know if this is something that can be looked at by the technical team? That appears to be a bug to me, more than just incompatibility. Or at least the BIOS should prevent the use of C-States (or maybe these specific settings) when XMP is enabled.

Also, I would like to add that from what I can remember from my previous build which involved an x99 Prime Deluxe II with an i7-6950X processor I didn’t have any problems having C-States and XMP work together!

Given the system is running XMP (it is overclocked), the default voltages may not be sufficient for stability when the CPU comes out of power saving modes. You can debug by tuning the voltages (Vcore, VCCSA, VCCIO, Cache voltage, VCCU) somewhat. With increased data rates, you're eating into the margin for stability.

[Thireus]

Raja@ASUS wrote:
Given the system is running XMP (it is overclocked), the default voltages may not be sufficient for stability when the CPU comes out of power saving modes. You can debug by tuning the voltages (Vcore, VCCSA, VCCIO, Cache voltage, VCCU) somewhat. With increased data rates, you're eating into the margin for stability.

Thank you Raja. I will try to tweak the Voltage and see how it goes.

With stock CPU clocks the system is stable with XMP. But now that I'm now trying to push it to 4.4Ghz the system freezes just like when C-States were enabled, it's just that it takes much longer to happen (maybe 4-5 hours).

VCore: 1.100V - That one I'm pretty sure it's alright, if I set it too low I have BSOD and/or Prime95 computation errors. As for now I believe I found the right value for it.

VCCIO: Default readings seem to be 1.040V when CPU is under load. This is the first Voltage I'm trying to bump.

VCCSA: Default readings seem to be 0.864V when CPU is under load.

Cache voltage: Default readings seem to be 1.048V when CPU is under load.

VCCU: No idea what this voltage is for. I can't find it in AIDA64.

I'll report back if I find any stability improvement.

[Thireus]

I would like to add that people are having similar freezing issues on the following threads:

https://rog.asus.com/forum/showthread.php?97318-UEFI-1003-for-the-Rampage-VI-Extreme-Changes-are-fre...
https://rog.asus.com/forum/showthread.php?98662-Rampage-Extreme-VI-causing-computer-freeze!

They might not all be related, but there is a good chance some of their issues are linked to what I found and detail in my previous posts.

[Silent_Scone]

Thireus wrote:
I would like to add that people are having similar freezing issues on the following threads:

https://rog.asus.com/forum/showthread.php?97318-UEFI-1003-for-the-Rampage-VI-Extreme-Changes-are-fre...
https://rog.asus.com/forum/showthread.php?98662-Rampage-Extreme-VI-causing-computer-freeze!
https://rog.asus.com/forum/showthread.php?46997-Asus-Extreme-Rampage-IV-freezing

They might not all be related, but there is a good chance some of their issues are linked to what I found and detail in my previous posts.

The first two were resolved by flashing to the newer BIOS revision available at the time, the last link is not even on this platform. Safe to say they're not related, unless you're encompassing all memory instability problems under the same roof.

It's also worth pointing out that I'm not aware of anyone else, including myself that has had to adjust this setting in order to maintain stability.

[Thireus]

Silent Scone wrote:
The first two were resolved by flashing to the newer BIOS revision available at the time, the last link is not even on this platform. Safe to say they're not related, unless you're encompassing all memory instability problems under the same roof.

It's also worth pointing out that I'm not aware of anyone else, including myself that has had to adjust this setting in order to maintain stability.

Hi Silent Scone,

Thank you for the clarification, indeed the last link was wrong. It is not often clear what changes Asus makes when they update their BIOS. As you can see the C-State settings set to "Auto" seems to be in fact "disabled", so maybe on old version this setting set on "Auto" was in fact "enabled"... who knows! So I believe that might be a combination of settings that on stock (set to Auto) are enabled or disabled and cause instability.

Are you saying that on your board with XMP enabled and C-State enabled your system doesn't freeze after long period of time? What config do you have?

If you've read my previous posts, I mention that on stock settings the system is perfectly stable. On stock settings + XMP, the system is also perfectly stable. Only when C-States are enabled with XMP, the system freezes after several hours.

[Raja]

You may need to apply more Vcore. One can never "suppose", as the rise in required Vcore can become non-linear in respect to frequency (and can also change when other domains are overclocked). General method is to find the limits of the cores, then add in xmp. That way, you have less to debug when faced with instability. The Broadwell-E, and Kaby Lake OC guides on ASUS Edge Up both detail sound methodology for overclocking.

[Thireus]

Problem solved, and lesson learned in the process:

1. The instability issue was due to an addition PCI-E 1Gb Ethernet card... The funny thing is that the card is working fine and has been working fine for years. I believe it just doesn't like this motherboard and CPU. My previous remarks on this thread are also still relevant, as for some reason the card was causing these freezes when any kind of overclocking and/or XMP + C-States was used. I got rid of it now, and since then no more freezing issues. C-States enabled, XMP enabled and CPU overclocked without any problem.

2. The issue had nothing to do with Voltage tweaking (I tried, it didn't help).

3. Next time I'll probably setup everything on a test bench and will make sure to reach a stable configuration before plugging additional devices. That would have saved me weeks of debugging.

End of the story (I hope), topic closed.