Sorry I would have been more descriptive above but I was in class while I typed that and the bell rang so I didn't have enough time.
Anyway, I had taken apart my comp to replace an old IDE cable with a newer rounded one, and to apply MX-2 thermal paste to my proc which previously had AS5. Anyway it turns out that somehow during that process one of the wires that plug into the HD Audio connector came loose and I guess it must have made contact with the mobo because all my major hardware was shorted out...
At first I didn't know I had shorted it and I just kept pushing the power button in frustration, and each time the fans spun up and my cathode turned on for about 1 second then everything shut down. Then I discovered that by pushing the power button again and again really fast I could "trick it" into staying on, but it still wouldn't even POST let alone boot up. So then I thought the PSU was bad and I almost sent it out for RMA, but I tested it with the pin test and it worked. (If you don't know, the pin test is when you use something metal like a paper clip or a pin to connect the green and black wires on the 24 pin mobo power cable, which should trick the PSU into turning on even though it isn't hooked up to the mobo or anything. If it works, then it's not a bad PSU from my understanding.)
So then I figured it must be my other hardware that was ****ed up so I took out everything except the mobo, RAM, CPU, and GPU and tried to turn it on, same thing. Then I tried it without the GPU, only mobo, RAM, and CPU, still same thing. Finally after removing the CPU it did turn on but it still wouldn't POST (obviously) and there wasn't an image on the screen when I tried it with 2 different graphics cards.
So then I knew my CPU must have been shorted out. I wasn't sure about the mobo or GPU yet though. So I took my GTX over my friend's house and tried it in his PC... it didn't work. So then I knew my GTX and CPU have both been fried. Just to be on the safe side, I also RMA'd the mobo. Assuming all were fried, that's about 800.00 in damages all because of one stupid wire. Luckily everything was still under warranty.
Since you said that when you try to turn yours on, nothing happens except the fans spin up for a second and then it shuts down, I'm thinking maybe one or more of your parts have been fried or were dead on arrival (DOA). So I recommend using the pin test to test your PSU if you haven't already, and if it works with the pin test then you'll know it's not bad. Next try to boot it up with minimal hardware... just mobo, CPU, and RAM, but connect a fan too so you know if it stays on then the fan won't stop spinning. Each time it doesn't work remove another part, until it does work. You could also try out your graphics card in a friend's PC like I did just so you know if that's working at all. Same with RAM, HDD's, etc.
Another thing, take out the CPU and inspect all the pins very closely. On mine, two were discolored as compared to the rest of them, leading me to think it was shorted out. Also inspect your mobo for signs of a short.
Good luck.