I have a 2007 MBP Model - 20MA896LL. Pressing the power spins the hard drive, but snow leopard does Not boot up--the screen remains black. I have attempted to reset the PRAM and the SMC. Both had no effect. My suspicion is that the problem is somewhere on the motherboard.
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The night before my MBP did not boot up, I ran a full Time Machine backup (excluding the Dwnlds fldr). I shut down normally. The next morning it would not boot up.
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The night before my MBP did not boot up, I ran a full Time Machine backup (excluding the Dwnlds fldr). I shut down normally. The next morning it would not boot up.