Messages

1

Hardware / Re: PC instant hardware shutdown if rendering with hyperthreaded Epyc 7773X CPU

« on: 2025-02-20, 13:55:00 »

Hi,

Thank you for the quick responses, I appreciate it.

In this case, we ran OCCT to stress test the CPU and it endured 20 minute ordeals just fine, full blast on all threads. But opening a scene and rendering for under 10 minutes + denoising was instant crash, repeatedly and consistently. Any ideas why the two situations produce different results, and how turning off hyper threading solved it?

2

Hardware / Re: PC instant hardware shutdown if rendering with hyperthreaded Epyc 7773X CPU

« on: 2025-02-20, 13:22:03 »

Surely that's not correct. The makers of the machine suggested kernel panic, for instance. Cpu cores were monitored and never exceeded standard values. The only change in the machine was swithing the cpu itself, RAM and PSU was identical.

3

Hardware / PC instant hardware shutdown if rendering with hyperthreaded Epyc 7773X CPU

« on: 2025-02-20, 10:23:44 »

Hey all,

We recently switched out a cpu from Epyc 7373X to the 7773X, which has 64 cores / 128 Threads. It passed all cpu stress tests, but during Corona rendering - and it seems particularly during denoising with High Quality denoiser - the machine panics and shuts off. I don't mean blue screen or Windows performing a shutdown, the power goes straight out, dead.

After trying this multiple times with the same shutdown results, we turned off hyperthreading in the BIOS which stopped the crashing. However, the lack of Hyperthreading loses about 16 percent performance as verified by Vraybenchmark and Passmark tests.

We'd love to switch the hyperthreading back on. Is there any way?