I think the common problem is with STEAM. It only crashes on STeam games. The effect is instant OFF straight to black screen.
I have had it on a few varietys of STEAM games. Men of War final assualt on steam and Just Cause2 and others.
Its not temp and its not graphic card drivers. I am not sure if it is a hack from other players like the old nuke one a few years back that made your pc crash through chat programs. In any case I would like STEAM to take notice and check why this is happeninig as it is a real pain. Funny thing though I have found if you dont load from a save game occasionally it will not do it. but only if you start new levels each time and not a saved game. Also It could be related to running trainers in the background?
Can not comment on men of war, but Just Cause 2 is a game I have played a fair bit of.
137 hours of destruction and playing with random in game elements that entertain and I have yet to see it crash(over about 4 computers with Intel, AMD and Nvidia). If you think its the trainer, try with it off.
As said, in steam right click your game and select View Forum and it will take you to the steam forum where you may find others with the same issues.