Need help getting a Western Digital drive to boot

[dunnstable]

I'm at my wits end trying to solve this. Maybe someone here can help.

I bought a 750GB 7200 rpm Western Digital Scorpio Black from Other World Computing. I installed Lion (10.7.1) on it in an external enclosure, copied everything over, and booted from it to make sure everything worked. Then I installed it in my MacBook Pro. The system recognises the drive, but stalls out trying to boot. In verbose mode, it stops at "still waiting for root device". This happens whether I use the main or recovery partition.

I then connected a MacBook to my computer via firewire, and it booted off the Scorpio Black without a hitch.

So in a nutshell, I can boot from the drive in an external enclosure, I can boot another computer from it while it's installed in mine, but I can't boot my computer from it as the internal drive. Any thoughts?

I've covered all the basics: the drive is properly formatted (GPT and HFS+ journaled); I've reset the PRAM and NVRAM; I've tried safe boot mode; I've run disk utility on it, both from the MacBook and when booting my system from an external drive (no problems found); and, when I boot from an external drive, system profiler identifies the Scorpio Black under Serial-ATA, and all the fields are correct and show no problems.

Thanks for any help,

Dunnstable

 

[Detrius]

Can you still boot from other HDs connected to the internal SATA? If not, it could be the cable.

 

[dunnstable]

Can you still boot from other HDs connected to the internal SATA? If not, it could be the cable.

I haven't checked that, though I might just restore the previous drive and check. Would it still be possible for the cable to be off if I could boot an external computer off the drive installed in my system via firewire?

Cheers,
Dunnstable

 

[Dhelsdon]

If you can boot another computer off the internal SATA then it's not the cable.

 

[Detrius]

If you can boot another computer off the internal SATA then it's not the cable.

Agreed, but there's the possibility of misinterpretation of what's going on, so I aimed for something simpler.