Updated TLDR: high-res texture installed and ultra graphics setting at 3840x2160 makes my 3080 shutdown. Happens only when playing D4. It seems uninstalling high-res texture pack, limiting GPU core clock under 1700 MHz using MSI afterburner, making GPU fan running at higher rpm, and D4 graphics setting at high work for me so far.
My PC is Alienware R12 with RTX 3080. So I don’t know if my 3080 is asus or gigabyte brand or something else. This one I bought about two years ago and I’ve been playing games like cyberpunk, god of war, etc just fine so far. I was playing D4 and suddenly my display went black. I saw artifacts (small red blocks) all over my display for 2~3 seconds before display went dark. PC was still on and fan was running. Holding power button didn’t do anything. Only way to get the PC back is to force power down by disconnecting power cord and wait for some time and power back up. This happens ONLY when I play D4.
I don’t remember all the D4 graphics settings but I do remember High-res texture installed, foreground fps was cap at 120, HDR on, DLSS balanced and at 3840x2160. I didn’t touch anything else.