I upgraded my MacBook Pro from a 120GB Fujitsu to a 500 GB Western Digital Scorpio Blue drive (totally bare from Amazon, just the drive in a plain brown box). I followed the directions provide by Apple, this is not a hard procedure.
I bought the 5000 rpm drive because I mostly care about reliability, low vibration, low temperature, and capacity. From what I read in this older MacBook the 7200's effective performance boost is very small and some 7200 drives have quite a bit of vibration (seems idiosyncratic).
I won't repeat Apple's directions, except to say they left off one little bit. I think this set of directions is more complete.
Briefly then ...
- I considered creating a disk image clone on my PPC iMac then using firewire disk mode on the MacBook to clone the image over. Andrew, who is generally reliable, warned me of some issues related to using a PPC to clone an Intel Mac drive (endian?). I had a very cheap 2.5" USB enclosure I'd used with a 80GB drive; it worked perfectly well with the 500 GB drive. I did discover that Intel and PPC Macs use different partitions for their boot drive. Intel Macs default to GUID partitions, PPC default "Apple partitions". So maybe that's the difference Andrew warned of. I did all the partitioning and cloning from my MacBook.
- I used Bombich Software: Carbon Copy Cloner  to clone from my MacBook. It took about 2-3 hours; it would have gone faster if I'd remembered turn off spotlight when cloning.
- Apple's directions omit one key step and tool. You need a T8 Torx driver to remove the metal shell that's wrapped around the disk. Maybe if you buy the replacement drive from Apple it comes with the shell? Anyway, if you have a Torx driver it's an easy task, but if you don't you're stuck.
- Apple's not kidding about the metallic foam shield that's glued on the RAM cover you remove. It's not easy to get the shield back on, you need a non-magnetic plastic card to push it down so you can get the metal band back into place.
The first boot seemed to take an eternity. It was much longer than usual. I think the systems was adjusting to the new drive. Once it started it rebuilt some caches then completed. I almost gave up -- so be patient.
So far so good. The drive is quieter than the original Fujitsu and it feels more responsive (could be imagination, it's a 5,000 not a 7,200. I might put the original in my mother's Mac Mini, though if I'm going to bother with that hard to service job I might as well buy another 500 GB drive.
Now I can carry more media around, and I can play with more virtual machines...
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