I played last night for about 5 or so hours on my PC. Ran fantastic, great frame rate, smooth the entire time. I tried to play today and it's completely unplayable. The frame rate is like 3. When I boot the game, the menu screen looks like all is good for a few seconds, and then, the frame rate plunges to next to nothing. If I load a game, same experience. I uninstalled and reinstalled but that didn't help anything. I have no idea what could have happened, but it's totally unplayable. This isn't like a "boo hoo I'm only getting 30fps" kind of thing. It's at about 3 or so, and even the main menu shows extreme lag and a barely animating/moving space ship. Any ideas what to try? Again, last night, played 5 or so hours with fantastic frame rate and zero issues at all. I don't get why one day it would be fine, and the next it would be unplayable.
Note: I tried other games in the Epic store (Operencia), as well as other games on Steam and they didn't have any issues. So I believe that would rule out an issue with my graphics card or something having changed with my drivers or whatever preventing intensive 3D games from playing well.
Note 2: I've tried all permutations of Windowed modes. I've tried vsync on/off. I've tried lowering the resolution to 1080x720. I've tried resetting the settings to default. None of it had any impact at all, like not a single bit of improvement whatsoever even on the main menu.
My machine:
Win 10x64 Pro
Geforce GTX 980
Intel i7-4790k
32GB RAM