Game Freezes!

Okay, so I got like no help from my last thread, so Im posting again, cause I really want to be able to play, Im having this problem, pretty sure its my comp, where everytime I join a game, about 3-5 minutes into the game, it freezes and all I can do is shut down my computer, and restart it..
I've played for like three months without troubles, it's just the last 2-3 days.
It really sucks, I wanna play so much..

I just need a solution to this so I can continue playing to great game.