I am currently experiencing this bug. Its frequency is varied. SOmethings I can play for hours without issues, but other times it comes every 30 minutes. I am currently on a 32-bit system if this helps at all.

One location I can easily replicate it is at Chernaya Polana. This city always causes this issue where textures do not render properly, when looking at a door I cannot tell if it is open or closed, and when I enter a building the walls become invisible.

I use to be able to do the SHIFT - FLUSH, and this would typically give me another 30-90 mins before the bug occurred again, but in the last 24 hours it has not been rectifying the issue.

Please let me know if you require any information.

-Billy Pilgrim