Cannot boot from 750GB Western Digital Scorpio Black

Question

I just installed a new 750GB 7200rpm Western Digital Scorpio Black in my early 2008 15" MacBook Pro (last pre-unibody). I can boot the computer from the Scorpio Black when it's in an external enclosure, I can boot another computer, a MacBook, from the Scorpio Black via firewire while that's installed in my MacBook Pro, but what I cannot do is get the MacBook Pro to boot off the Scorpio Black as the internal drive. It will recognize it and show the main and recovery partititions, but it won't boot the OS (10.7.1.).
Here's a rundown of the installation and troubleshooting steps I've taken:
1.) Installed the drive in an external USB enclosure, formatted GUID partition table (GPT), file system HFS+ extended journaled.
1.b) Downloaded and installed Lion (10.7.1) from the App Store, used migration assistant to transfer accounts from my (now former) internal drive, and then booted from the Scorpio Black in the external enclosure to ensure everything worked fine.
2.) Installed the drive via iFixit instructions. Everything fit properly and I double checked the SATA connector was seated correctly.
3.) Booted computer for the first time with the Scorpio Black. It stuck at a spinning wheel on a grey screen.
4.) Held down option key at startup -- the computer showed the main partition and the recovery partition on the Scorpio Black as the startup drive options.
5.) Tried the recovery partition -- spinning wheel on a grey screen.
6.) Tried safe verbose boot (command - shift - v) -- it interleaves "still waiting for root device" with "SATA WARNING: Enable Drive PHY PM failed" and "SATA WARNING: auto-activate failed".
7.) Reset PRAM & NVRAM -- no joy.
8.) Connected the MacBook Pro via firewire to a Core 2 Duo white MacBook also running 10.7.1. The MacBook recognized the drive and in Disk Utility, I could see all the partitions on it.
9.) Ran repair volume (for the drive) and repair partition (for my main partition) from disk utility on the MacBook -- it said everything's fine with both.
10.) In system preferences, set the Scorpio Black as the startup drive for the MacBook.
11.) Astonishingly, the MacBook booted up just fine off the Scorpio Black in the MacBook Pro. I logged in, opened a few photos and played a video. Everything worked just peachy.
12.) Booted the MacBook Pro off my old internal hard drive, now in an external enclosure.
13.) Disk utility sees the internal Scorpio Black, and reports everything is fine with the volume and the partition.
14.) System profiler says everything is fine when I check under SATA. SMART status is verified.
Which brings me to step 15: admit defeat and ask for help. Any suggestions? The exact model number of the drive is WD7500BKPT. I purchased it from Other World Computing.
Thanks for any help.
Cheers.

Answer 1

I actually first replaced the stock hard drive with a Western Digital 500 GB Scorpio Blue (i.e., a 5400 rpm drive). Here's what I can tell you about all three.
First, I didn't notice any difference in noise, vibration or power consumption between any of the drives. The computer felt stock with both of the Western Digital drives.
In terms of speed, my understanding is, all other things being equal, a larger drive is always faster than a lower capacity drive (I believe that's because more of the data is on the faster rotating outer areas). That being said, the step up to the 750GB 7200 rpm Scorpio Black was a bigger one than to the 500 GB 5400 rpm Scorpio Blue -- it gave a noticeable bump in performance. Opening my Aperture library and browsing photos went from sluggish and borderline unusuable to acceptable, or even good.
Bottom line, it's not a solid state drive, so don't expect MacBook Air levels of responsiveness, but I can wholeheartedly recommend the Scorpio Black.