About a week ago, I updated to new AMD drivers and my once stable Rx580 Sapphire Nitro+ 8GB decided to stop working in any graphic intensive games. I've tried about everything and nothing has worked. Also, I can't even play non-intensive games like rocket league for more than a couple minutes without it black screening.
Specs of PC
Things I've tried
Try installing the previous AMD Driver you had and see if that fixes your problem in case it is a bug in the latest AMD Driver for your RX580.
You can download the past ~6 months of AMD Driver from here: https://www.amd.com/en/support/previous-drivers/graphics/radeon-500-series/radeon-rx-500-series/rade...
It is possible the latest driver is not making the GPU fan to work at full speed when it is overheating thus shutting down your computer.
I would download OCCT and run both the GPU and PSU tests to see if your GPU card or CPU is overheating under stress.
Keep a close eye on both Temps and PSU Outputs while the test is running.
I have the exact same RX580 version. Before that, I've had the MSI Armor RX580 - worst of them all. It had bad cooling, high Temps, loud fans as 10 full spinning fans. Just horror. The Nitro+ is great. Had a Nitro+ RX570 8GB, no issues. Sapphire's take on AMD cards is the best by far, on par with Strix for Nvidia. The 570 benefited from the 20.4.2 driver, newer caused issues like crashes and random reboots etc. The 580 is great with 20.8.3 in my case. Compared to 20.4.2, I get FPS boost in most games, especially Fortnite (even AMD states Fortnite improvement with that driver 20.8.3.) where I get 150+FPS 1080p epic VD, all low off, with 20.4.2 only max 120 and stutter and FPS drops less than 60FPS.
The nitro+ has dual bios. Meaning you can switch between them via the little lever (silent left, oc right). Before flashing the bios via ATIflash, I had issues like monitor couldn't do 144hz, the option in windows wasn't even there. Next 0db mode was off, high temps. So I tried the 4 valid bioses on techpowerup, and the second newest from 2017 fixed it all for me.