MemTest86+ or MemTest86?
I suggested both, but 1 was by accident.
Memory corruption could also be from the GPU, but I wanted to make sure the memtest was done properly
Run Furmark to test your GPU. Furmark tutorial
NoteRun Furmark for around 30 minutes
WarningYour GPU temperatures will rise quickly while Furmark is running. Keep a keen eye on them and abort the test if temperatures rise too high
Run Furmark when I first got this graphics card for about 4 hours ... no issues.
When exactly is the crash usually happening?
It happens when I watch youtube ... but considering how infrequently it happens it might be that its just what I do with this PC the most (I tried running youtube playlist overnight and I can get more than 24 hours of youtube playback without a crash)
I'm actually not sure, but the only things left are the CPU, motherboard and PSU.
Although I would doubt the CPU, because it is the most stable generally.