I recently moved two perfectly good PC's in a corporate environment. PC-1 went to a conference floor for a demo, PC-2 I justed moved from one cubicle to another. Both are IBM NetVista's.
Now both won't boot up. Neither was mishandled, just placed gently on the floor (that has a carpet on it, just your basic office carpet). Could that have zapped them? I hope not, since I'm a consultant here :-(
For PC-1, when I moved it to the conference room, at first it didn't boot. 2nd time though it booted ok. When I took it back and put the machine on the desktop, now it won't boot.
For PC-2, the office moving company moved my PC overnight, set it up on the desktop and it booted up ok. Then I moved it to the floor to save space - and 5 minutes after it had worked, now it won't boot. PC-2 lays flat on the desk and I'm in no position to crack the case, mainly because everyone's watching (my cube wall is three feet high :-(
For PC-2, now it says "No operating system found". PC-1 doesn't say that but it never makes it to the boot sequence, it just loops.
I had the same thing at home, to fix it I just opened the case (IBM NetVista) and made sure everything was tight, and that fixed that. So I opened one of the cases here, pushed on the cables / hard drive to make sure it was tight, now nothing.