Question Crashing under load, not PSU or GPU?

Jamessuperfun

Distinguished
May 27, 2012
84
0
18,630
Hi,

I have a system which I recently upgraded to a 12700KF. It's run fine since launch weekend, but now crashes as soon as it's given a little bit of load. I have a fair amount of old components lying around which I've been testing with.

At first I suspected the RAM, so I ran some memory tests, which failed. I'm not sure what's changed, but I've removed all but one stick and consistently pass Windows memory checker but reboot about a minute into a game. Reducing frequencies doesn't help. It seems to be crashing sooner the more I test, but it doesn't matter which stick or slot I use, the result is the same. Passes memory tests, crashes the minute I start a game. Frustratingly the motherboard doesn't seem to properly apply my settings sometimes, just sits on a black screen after saving and exiting BIOS.

Swapping the 3080 out for a 1080Ti resolves the problem, but the 3080 is rock solid in 2 other systems. I took it somewhere to test and it ran fine, also hooked it up to an old motherboard (different RAM, CPU, SSD) with the same power supply, which runs fine. This makes me think it isn't the GPU, RAM or power supply.

I'm at my wits end here, having spent an entire day messing with it. The system worked fine for a few weeks but now will not run games with the 3080 in it, yet is fine in other configurations, including just changing to a 1080Ti. Any ideas?