Pc freezes when all CPUs are enabled

[cuthulhuu]

Hi, So the thing is that my PC freezes when Memtest runs with all CPUs enabled. Already checked motherboards known to be incompatible with memtest and I didn't find mine mobo on the list. Test runs fine when only one CPU is enabled but when other cores are enabled it fails randomly by freezing PC or rebooting it. I've flashed latest stable BIOS but it doesn't help. PSU gives stable voltages on load and when idle (tested for the whole week).

Mobo: Gigabyte 990XA-UD3
BIOS: FD – latest non beta
CPU: AMD FX(tm)-6300
RAM: Crucial Ballistix Sport 24GB (8 GB +8 GB +4 GB +4GB) 1600mhz

Any ideas what might be an issue? The reason why I'm trying to run Memetest are random reboots of my PC when it runs for many days as an quasi media server. Sometimes it reboots after 10 days and sometimes after 18 days.

[David (PassMark)]

The GA-990FX-GAMING board is known to have issues. Which isn't your board, but in name at least not far off it.

But these multi-threading UEFI BIOS bugs generally show themselves very early in the test run.

In your log I see it got to test 7 before the log stopped (I assume the machine crashes during or after test 7). So maybe it is a real hardware failure under load.

If it only crashes once every two weeks it is going to be hard to debug.

[cuthulhuu]

The thing is that it crashes once every two, sometimes every three weeks when idling or when under load . Any clues on how to try to debug that?

[David (PassMark)]

There is a background level of radiation that can cause problems for long term stability of regular computers. (ECC ram was created to help with this).
See,
https://en.wikipedia.org/wiki/Soft_error

• Have a look in the Windows event log for anything strange.
• If it was really important, you could connect up an inline PSU tester to look for spikes and brown outs. Then leave it running for a few weeks.
• See if any BSOD records are being created (Nirsoft's BSOB tool is good for this).
• There is some change it could be a device driver bug. But if it crashes in Memtest86 as well as windows, then this is less likely. Doesn't totally rule out a firmware bug however.
• If you can reproduce the error quickly with MemTest86, start swapping components. RAM first, then CPU, the motherboard & PSU.