intermittent macbook

for some reason my macbook shuts down randomly. i have checked apple support and downloaded the firmwire update which claims to fix this problem but for some reason it is still shutting down randomly. any ideas on why and how to fix this problem as it is beginning to send me insane!!!

probably a question for the Genius Bar at your local Apple Store. Most likely a hardware failure, which will require some warranty work.

figures! thanks, confirmed what I was thinking

recently had my macbook repaired. The logic board was replaced, but unfortunatly this has not solved the problem :/