Since Hard drives have gotten so large recently, here is what the manuf's do:

They partition the hard drive - the partition will only be 15M or 1G in size (small pototoes if you have a 250G hd) and the small partition holds a factory disk image, or a compressed version of the same.
When the manuf. gets the computer back to fix, all they do is run a small program that formats the large partition (your C drive), and re-installs the factory windows install from the data on that small partition. it makes 'computer repair' very quick....becuase they dont care if they lose your data or not. Every dell I've seen in the last year ships like this.

The small partition is not usually obvious, unless you know where to look, and since 95% of your HD is available to the user, they never complain about the slight loss of storage space.

As far as I would guess - I'd double check your power supply, they now make 3 or 4 (or 6?) different voltages - all of which need to work for the computer to run. And the switching nature of these power supplies means that it isnt normally testable with just a VOM while disconnected - you need to put a load on each line to make it work properly.

-John

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