Materials not loading in tf2!!

[Acid Green]

Some times when i play in tf2 (most of the time on 2fort and dustbowl) everything turns black after about 20 minutes...
it doesn't do it on lazytown or gravelpit as much as those two maps...

I have tried restarting the game
restarting my pc
reinstalling the game

AND BLAH

any ideas

 

[MrFroho]

what kinda graphx card do you have?

if u have nvidia SLI, i'd disable SLI.

 

[Acid Green]

ty but i found out how to solve it

just close out of some programs such as xfire