Yes you should be able to just tell them that your computer is fried and you cant use it. But if your computer doesnt work. trouble shoot it first. As in go through everything and ask questions to pin point what is not working on it. if all else fails and the mobo or cpu is fried, then at least you have everything, cd drive, Harddrive, powersupply, ram, and case. Then you could just go buy another micro atx mobo with cpu for about $150 - $200 depending on what you get. Then you have yourself a working computer

The main things I have had go out on me are powersupplies, mobo's, and ram.
I took some pics and I hope this helps
Here are the power connectors

The powersupply should come with the 20 + 4 pin connector that connects to the 24 pin plug, then it should have an extra 4 pin connector that plugs into the 4 pin plug

(this is the fried mobo that came out of the gateway)
This is where the harddrive, cd drive, and hot drive bays are

(I have a different mobo in my computer the one that came with the computer had water spilled on it and fried it)
I dont know if you got any sata cables with it but this is the sata cable needed to plug in your harddrive, Kind of a design flaw with this computer, it is hard if not impossible to put the side panel back on with out this 90 degree angle plug.
And here is the hot drive bay power connectors that plug into the powersupply
and then the power supply has to hook into the the motherboard only by the looks of it am i correct?
I dont think I answered this but no the power supply plugs into the motherboard with the 24 pin connector and the 4 pin (Shown in the mobo pic), but the power supply will have other plugs on it for the harddrive, cd drive, ect ect.