My 15"MBP, less than a year old but pre-retina display model shut down today while it was powered up but idle. I powered it back on, however now it won't boot. I have run through everything suggested here: http://support.apple.com/kb/TS2570 without sucess. The problem I am having is that I can't get the computer to boot to a 10.4.8 or to 10.6.3 system DVDs or to a 10.6 retail version. The computer just sits there at the Apple logo forever. It won't do a Network boot either, the Earth logo flashes mutliple times then I get an Apple logo with status bar beneath it. The status bar gets to about 30% then disappears, after which the computer powers off. It is totally stock, never had the case open. Any ideas would be appreciated.