Black screen (nothing that said before worked D:)

[Yak'All]

this is anoying already, i tried everyting some of you guys said i had to do, but always every time since i uploaded my vidio drivers the game just wont work, the main screen is good, the loading is good, when it finish loading, the sound starts being anoying then the screen turns black and the sounds stops (cause the computer stops working D:) any ideas of why is this happening??

PD: this happens with L4D2 and Alien Swarm, is there something in common?

[m30w]

Did you try verifying game cache? Right click l4d2 > properties > local game files tab > verify...try that and then try it again.

[Yak'All]

done already :,( same thing happens

[Slim Shady]

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