Horrible stuttering after entering a new area, AMD/Win10

Started noticing this really badly this league, enter a new area and it stutters like absolute mad, doesn't seem to stop, sometimes it'll taper off after a few minutes. FPS difference is literally 110 own to 50-60 with really bad stutter.

However if I close the client and relaunch it's 100% perfect again. All the stuttering is due to shader fussing I'm guessing as if I check my procmon I see that the game is doing a ton with "bundle"/"streaming" files, yet when I load the game fresh it doesn't mess with those files at all and runs great. Something is obviously screwed up with the texture streaming nonsense.