Left 4 Dead Crash Issue Solved!!!!!!!!!
Well, thanks a million to one of my best friend Zhen Yang, who suggested the best solution in the comment section (Kick The Zombies’ Ass) to prevent L4D from crashing randomly in game ^_^ This basically applicable to all core2duo and above users.
Click Option–> Video–> Advanced Settings–> Multicore Rendering–> Disabled
ENJOY PLAYING WITHOUT CRASHING~~~~~