Some objects missing textures after extended play

GrowlyWalrus

Hey guys, I suspect this may be related to the memory fragmentation issue others have reported, but I'm having a rather different symptom. After about 2 hours of play, some of the textures stop appearing, most noticeably the alien's skins - they start appearing as nothing but black blurs. At first I thought this was some new camo upgrade, but it seems that other objects are affected as well. Right before I stopped (oddly the game still worked fine in this state, I just couldn't hit anything since some of the aliens stopped appearing entirely), it'd gotten to the point where the animation for the IP wasn't playing while I was spawning, and my character was not visible in it. I've attached a screenshot of the aforementioned black effect on a sentry battery and the character model's gun. System specs also follow. I was running in DX9 full screen mode.
http://steamcommunity.com/id/growlywalrus/screenshots/
Windows 7 64bit
Driver packaging version 12.104-130328a-159787C-ATI
AMD Radeon 7800 series, 2GB DDR5 vram
i5-2500 @ 3.3Ghz
8GB DDR3 system memory

GhoulofGSG9

Any log?

GrowlyWalrus

Sorry about that, here's the latest.