ok download the latest beta driver from below link, it has a fix for bf3 ertc crashing to desktop etc it maybe relevant.
also run windows update to see if it picks up new driver for the intel card as well
done and done.. The game is not crashing or disappearing anymore. FPS is 50+ in sector X (only 8 players online) when i log in the game, but the longer i stay logged on the more it drops. I am going o buy a laptop cooling pad just in case and test it.