Just got a Seagate Momentus 7200.4 500GB to install in a white MacBook Core 2 Duo 2.0Ghz. The MacBook can read, write, and format the drive (connected as a USB external) with no problem. It can't seem to boot from it or install OS X to the drive. I've tried: 1) cloning the current drive using disk utility's restore option while booted from a 10.5 install disk--Seagate drive will not boot after clone even though the MacBook sees it as a boot device when looking at the startup disk options while booted from the 10.5 disk. 2) Time Machine restore to the Seagate drive--fails every time with a long error log. 3) Clean install to the Seagate drive with a retail 10.5 install disk--install fails every time. The drive could just be defective but I've seen a lot of defective drives and it doesn't feel like that's the case. I haven't run any hardware tests on the drive. (Anyone know if an Intel Mac will boot Seatools?) Anyone else have any experience with the Seagate Momentus in an older Core 2 MacBook? I seem to vaguely recall reading on Apple's store page around the time I bought the MacBook that the max HDD supported was a 320GB (a size that at the time was larger than anything available to consumers). Not sure if that is the case or not. Any assistance/advice from the community would be appreciated.