We can go through a couple of things to reduce the project overhead to get it stable enough to be able to figure out what’s going on. It’s definitely looking like an environmental graphics issue in this case. So we’ll dig deeper in the environmental possibilities here.
If you’re using Game Ready drivers, swap them over to Studio drivers for more stability in UE.
Try restoring the default global settings in the Nvidia control panel, this sometimes corrects issues based on the settings forced here.
Are you using any overlays/GPU utilities or anything like Shadowplay, Rivatuner, or afterburner? They can also cause this.
I have a thread where I go through many ways to lower graphical overhead and fix a couple of GPU side issues. However, there’s a TON more possible answers littered through the post by other users.
This sometimes albeit rarely, stems from failed graphics driver installations over time. Both AMD and Nvidia offer their respective driver cleanup utilities, I usually recommend it as a last resort. After cleanup, a fresh install of the most recent drivers sometimes fixes it.
If you cannot get all the way into the project to be able to change some internals, see if you can use the -D3Ddebug argument and change the startup level to something like the built in minimal_default. This will get us a tiny bit more info.
I know I threw a ton at you there, but this is one of those issues that can be directly caused by the geometry at play but also could totally be environmental. The move to SM6 has been tumultuous.