Oddhermit: There are a few options people've had success with -
Disable AA (and probably use an outside source of it)
If you can't run regular ubersampling smoothly, open the ini file "user in the config folder in the witcher folder in your documents folder
ctrl+f and search "uber" and change ubersampling to 1 and try that
I use the second method personally - you can sort of still notice the "grid" on some things in some lighting, but barely
Thank you for the second advice. I've put "1" on the ubersampling line and oO. I don't recognize my game. And the cherry on the cake? No fps loss \o/ .