[SOLVED] RX 580 Sometimes Crashing in Heaven or gaming, sometimes stable

Dec 19, 2020
I bought a used Sapphire RX 580 the other day, the guy told me he was mining for 3 months and decided to quit.
The card looks to be in good condition.
Now, when I run Heaven benchmark on ultra settings it will almost always go to a black screen and I have to restart the pc.
If I run it on high with anti-aliasing off, it will go on forever, no problems. If I go ultra settings with anti-aliasing off sometimes it will go for a few passes no problem, other times it just crashes at the start.

Furmark runs super stable on default 1080 settings, but as soon as I turn on MSAA it will crash.

I tried playing Cyberpunk on it on medium settings and I played like 3-4 hours no problem yesterday, but today it just kept crashing as soon as the game loads. (the actual gameplay, not the menus). Then a weird thing happened, it was like Cyberpunk broke the drivers. I was getting light artifacts in Heaven, restart didnt help.
I reinstalled the drivers to a an older version and I played CP for an hour no problem. Then I tried Heaven again and it ran fine for 30 minutes, then I turned Anti-aliasing on and it insta crashed.
The temperatures don't go over 55-60 C so it's not overheating. It's not overclocked. (in fact I tried underclocking , it did nothing)
It runs fine in Windows, playing video and all the other normal use.

I tried all of the above on both the silent and performance modes of BIOS. (it has a little switch for changing). No differences at all.

I have a Corsair CX500 psu, though I do have 3 hard drives, and SSD and 32gigs of RAM in it with an 4th gen i7.

Anyone have any idea what might be the problem?