Inability to boot from alternative boot devices

Question

Hi… I apologize if this has been covered, but my searching hasn't found anything definitive.
A friend asked me to replace the hard drive in his Macbook, one month out of warranty. The techs at Apple (I understand he went to a Genius Bar) told him that the hard drive is the problem on the machine.
The computer is a Macbook late 2008, and it's not booting. In an attempt to salvage some of the HD's data, I tried booting from an external, but no dice. The problem is, now I'm thinking it might be more than just the hard drive… when my hard drive crapped out on me, I was able to boot from my external, from a boot DVD, etc.
When I first got it, it would start up, go to a white/grey screen, and that's it.
Then I zapped the PRAM, and I started getting chimes, but that's it.
I held down option to get boot options, and was able to see my external hard drive, but never my boot DVD (this is not an OS X DVD, it's an 'emergency disc' with various software). It was also able to see my Macbook's HD, which I connected in Target Disk Mode. However, it was never able to open either drive. The cursor would show up on the screen, followed by the orange little FW HD icon, already selected (the Macbook has one FW port, so I was unable to connect them both at the same time), but that's it. Clicking, hitting enter, etc, did nothing. No discernible reaction.
Just for kicks, I reset the SMC. When I restarted the computer, I now got a flashing folder… which actually bodes well, as that's usually just a HD issue, not logic board (as far as I know). But when I rebooted again to try to boot from another external, etc, I got the white/grey screen again, and that's it.
So, my question is this:
Is there anything else I can try? Either to fix this or to eliminate HD vs. other components.
Is this just a hard drive issue?
If this is something else (e.g. logic board), what would it cost to replace?
One thing I found on Google mentioned that removing the hard drive, if totally dead, could possible fix this. Can this be? I mean, I'm telling the computer to bypass the hard drive entirely!
Thanks in advance… I'm hoping I remembered everything I tried.

Answer 1

Hi hudgie,
There's any number of situations that occur when a HD fails, having worked at one of those "Genius Bars" for a while I can honestly say that there's no across the board, failure indication. Some of the more common indicates were:
1.) Startup to a flashing folder with question mark
2.) Loud clicking/grinding noise
3.) No noise/responsiveness from drive
4.) System bus lockup / inability to launch startup manager / inability to boot from external source
It sounds like you're dealing with situation #4. When my HD failed in my MacBook Pro it did the same thing, the drive would lock up the startup sequence and prevent me from doing anything. When I removed the HD and attempted to boot from an external source it would then startup just fine.
I personally don't think you're dealing with a logic board issue, but the only way to confirm that would be to connect another HD to the drive connection and try to boot the machine. If the issue persists I'd even go so far as to replace the SATA connection cable and then point a finger at the logic board.
Apple offers a "flat rate" repair service for machines out of warranty but with no accidental damage, I believe the price runs about ~$350. If you're just replacing a HD or the SATA cable and drive it's much cheaper to do it yourself. If you determine that the logic board is the point of failure, then I'd go the route of having Apple do it for you. Especially because the repair service grants you a 90-day limited warranty on the machine.