I am experiencing this problem with an EVGA 1080Ti SC Black.
When I first installed this card, it displayed as GP106 [GeForce GTX 1080Ti]. I didn’t think much of it at the time since I was first assembling the rig. After some reboots and installing the rest of the cards, this card worked fine and was detected as normal.
Fast forward to yesterday and I am making some minor tweaks. My miner restarted, and has not picked up this card properly since. Can only get it to display as GP106.
I tried downgrading to the latest stable kernel, and tried NVIDIA drivers 455 & 460 as stated in posts above. Tried a new riser and even switched the card to a different power supply. Nothing. The problem is following the card.
Tonight, I will put the card into my gaming PC and see if it is hanging onto some weird OC setting. Otherwise I’m not sure what to do.