TF2 Crash problem

[BEn_2600+]

When i start TF2 i load the first game i find, it finishes loading and just before it goes into the game to play, it CTDs and shows the following error:

Spec is in sig, i have gone back to stock clocks, rolled back drivers to 8.2, changed NOD32 for kaspersky all of which failed to fix the problem

 

[BEn_2600+]

You've run out of memory... what OS are you using?

Try lowering texture quality and turning off AA, just to test if it helps.

Windows Xp x64 i have 4GB of RAM so i shouldn't have this problem i thoguth source based games didnt use that much memory

 

[BEn_2600+]

Looks like somethings not right.. Sat on the desktop over 3Gb RAM is being used