Doubt its the HDD. If the HDD was bad, you should still get a screen but with the error o/s not found or non bootable drive/diskette, or some other various error. More than likely, I would try to reseat the vid card, mem, CPU also check the amount of paste on the CPU (if he just put it on, that is), try reseating one at a time and see if that helps. I'm guessing he gets an orange light on the monitor or blinking light. If that doesn't help, next step is to remove EVERYTHING to a barebones system. Just have the vid, mem, HDD, and CPU only. No cdrom, floppy, keyboard, mouse, etc. Yes, you'll get a kbd error but right now were just trying to get a screen. Finally if that doesn't work, remove the MBD from the case and put it on something non conductive (like antistatic or rubber or whatnot, just not on the carpet). This is to make sure the MBD is not grounding out to the case. He DID use plastic supports for the screws?? Otherwise, he's probably gounding to the case. Main thing is, I would probably rule out the HDD. You could remove the HDD and see if you get a screen, though.
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