Screenfreezing. I can still play, but my screen is frozen. I tested around, and they only way I could play until I tried to test other settings again was with:
Display Mode: Flip fullscreen 1920x1080 render scale 25 (Later I tried to increase this to 100 and it froze again) frame cap 0 menu framecap 0 buffering 5 frames (this was the first option that made it even playable for me to change) v-sync off AA off low quality texture/shadows no AO
When you say that the screen gets frozen and yet you "can still play", I'm going to assume that you mean that the visuals become static, nothing changes, but you still hear sounds as if the game is still going on.
Your settings folder is C:\Users\AppData\Roaming\Diabotical (You can there by going to %appdata%/Diabotical in Windows explorer or in Windows+Run)
After closing the game, rename "settings.txt" in that folder to "backup-settings.txt" to reset your settings without losing them.
If that fixes it, send us the offending "backup-settings.txt" for analysis. You can send me this on Discord or you can put the context in a pastebin and DM me the link on Reddit.
If that doesn't fix it and you have the Nvidia overlay enabled, try disabling it.
If that still doesn't fix it:
Can you tell me if you are on a laptop?
Can you tell me if you on a setup where you are using multiple graphics cards simultaneously?
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