I came home to my MBP "dead" - it's a 2008 2.4 GHZ model. When I hit the power button I hear the cd drive do it's thing and the fans start to spin up, but there's no startup sound and the screen is completely dead. I've tried hooking it up to an external monitor but nothing. I've checked the battery - it's fine, and i've tried starting it when it's plugged into a power source. Nothing. Any ideas on anything else I can try?