Odd lag has appeared out of the blue.

My computer's comfortably ran this game for 150 hours, but when I turned it on today there was all this lag. During most of the game it was fine, but whenever the loading screen finished there would be some stuttering and, more annoyingly, whenever I opened the menu or changed a tab there. Going to the blacksmith is infuriating having to wait a couple seconds for each screen to load. Running around, fighting seems mostly fine though load times might also be a bit longer.

The computer's also fairly new--playing the Witcher is one of the first things I did after building it a month or two ago. 30 GB left on the SSD. I've read about microstuttering online, but that seems to happen at all phases of gameplay, whereas my issue is, like I said, mostly loading stuff on the menu tabs or the load page.

Does anyone know about this issue? I've reinstalled my Nvidia graphics drivers and verified local content on Steam, but no luck.

Cheers!