I have a 1080ti on riser . not mining anything yet, just booted up and after a few mins, sometimes 20-30 mins, the GPU temperature drops to zero and settings are grayed out on MSI afterburner - like it is detected, but somehow it's off. I swapped out with a different GPU (1070ti) and different risers and it does the same. this is on a fresh install of windows pro 10 build 1903. Geforce drivers 436.30 which is the latest. i uninstalled and installed drivers multiple times.

what could be causing the issue?