Left 4 Dead crashing! NEED HELP!

Left 4 Dead has been crashing lately for me and I don't know why. Here is the "problem signature":

Problem signature:
Problem Event Name: APPCRASH
Application Name: left4dead.exe
Application Version: 0.0.0.0
Application Timestamp: 492b66bb
Fault Module Name: client.dll
Fault Module Version: 0.0.0.0
Fault Module Timestamp: 4ac29d64
Exception Code: c0000005
Exception Offset: 002cac93
OS Version: 6.1.7600.2.0.0.256.48
Locale ID: 1033
Additional Information 1: 0a9e
Additional Information 2: 0a9e372d3b4ad19135b953a78882e789
Additional Information 3: 0a9e
Additional Information 4: 0a9e372d3b4ad19135b953a78882e789

Bye the way I'm running Windows 7.

So I lowered some of the video setting and I got this mother:

http://img199.imageshack.us/img199/5586/errorat.png

reinstall

Already did, bro. Twice.

Hmm well the error your getting seems like its from a corruption of game files, or have you overclocked at all?, it happens with me if i push it too hard.

No, I've never overclocked anything. I'm reinstalling it again from steam...we'll see.

Seems that the garbage can (which is usually spawned randomnly, is within or intersecting another object, which is usually a wall)

Im guessing that the crash appears in random games?