I have a MacBook Pro 15" 2.8 Ghz late-2008 model. I've looked up this problem several times but nobody seems to have the same thing - it seems to be going to sleep at random times without invocation, for a few seconds. The display goes black, and if I'm playing music or a movie it stops, and the backlighting on the keyboard dies. It comes back, but the problem seems to be getting more persistent, and can happen within 5-10 minutes - very counter-productive. I've tried all the standard fixes - changing energy saver preferences, switching the graphics card, resetting the PRAM, repairing disk permissions - and it doesn't seem to be making any difference. The main problem is that the timing is so random, and I can go for several hours without it happening, but then it will happen in a series of bursts. I've called Apple's helpline and it seems that I've only just run out of warranty on it - worse still, I'm in France for the next few months and don't speak much French. I'm not prepared to pay for a repair, so I desperately need to know if there is some kind of fix to this problem. Thanks in advance for help!