Thanks for viewing my thread. Forgive me if a similar thread exist somewhere. But I have a MBP, 2.93GHz, C2D, Mid-09, 17" model. It comes installed with the Hitachi 320GB. I have this Seagate 500GB. I copied all the data over using TechTool Pro. Theres a copier AND verifier on there. When I put the 500GB in my computer and tried to start it up, it paused for about 20 seconds, then a grey curtain came down over the screen and told me to power it off. I did, then quickly put in a OSX disc, went to see if something was wrong thru disk utility, and it told me it was having permission troubles, so I repaired those. I tried to start it again, and the grey screen came Much faster this time. So now im back to the 320 and wondering if anyone has a suggestion? I formatted the HD journaled Did a zero-out format I changed the name of the HD, but could that be an issue?