I replaced my the RAM in my MBP with 2 2GB DDR2-800. I then found that DDR2-800 is not compatible with my MBP and it didn't boot. So I put back the RAM that came with my MBP in. But now my MBP doesn't even boot... It emits 3 beeps, seconds later it emits another 3 beeps again. My MBP is the early 2008 model, 17-inch. Can anybody help me please because my warranty is over.