It happens while the logos are coming up (Crytek / EA / Cryengine 3 and bra bra bra...).

it freezes for a moment , 2-3 sec later it goes black and I can't do anything except reboot my PC.

but strange thing is... sometimes it doesn't happen and I can play the game without any problems. (Extreme setting)

After I tried again and again , I know that the game only freezes while the logos are coming up. if the game can run through those logos to the Main menu of crysis 2 , there're no problem anymore.

Why ? I think the problem is VGA Driver... or not ? or crysis 2 has problem with ATI ?

My specs.
Intel Core i5
AMD HD5870
Ram 4 GB
Window 7 Ultimate 32bit

PS. I'm sorry if there anything wrong with my gramma. I'm thai , but I try to make it understandable.