My brother's 2009 MBP 13" is having some serious problems. It wouldn't boot (question mark folder), so I popped in a USB with Lion and booted to USB, formatted harddrive, and installed Lion. Seemed to work fine, although took a while to install. Then booting to Lion was iffy, most of the time it would boot, but it would take a rather long time (over a minute). Once inside, it would work OK until a random spinning beach ball would come up. Happened a few times in under an hour. Restart and come back to Lion shows some preferences weren't saved. Thinking it's the harddrive, but I ran a harddrive diagnostic (Disk Utility), and it says it is fine. Now running memtest, but that looks like it will be OK. What else could be wrong? I need to run a full hardware diagnostic, but holding down D while booting does not do anything. No more warranty so I cant exactly drop it off at the Genius bar. Thanks!