system
A chat on subreddit /r/pcmasterrace
human
Just checked your post. I think you already found the issue is your GPU. The reason why stress test worked out fine can be the type of stress test you did. Maybe it is a shader issue and your stress test did not touch that part. It depends and usually this kind of issue is not going to be user fixable anyway.
gpt
Thanks, if it helps I used FurMark and Heaven for stress tests.