AlienWare x51 R2 - Computer not receiving power from PSU

So I have had my AlienWare X51 R2 for 1 year and about 20 days. It is barely outside of warranty... I got home 2 days ago to find that it was turned off but there was a very dim light on my power button, no other lights. I tried turning it on and the whole computer (Yes, fan and lights included) turned on for about as long as it took for me to let go of the power button. I have tried everything. I'm not even sure if this is the right place to be posting this but I hope so. I've tried skipping my surge protector and going straight into my socket, using a different socket in a different room, disconnecting everything and holding down the power button to rid of any leftover power, everything. My adapter, I think people call it a Brick, has it's power light on but my computer only has the power button light dim. The light on the back that lights up blue if it has power only lights up when I turn it on for the split second when I try to turn it on. My computer did not have viruses and was fully scanned every night at 2:00 AM by Microsoft Security Essentials. I have played games like Guild Wars 2, World of Warcraft, StarCraft 2, and ArcheAge. Archeage was the last and only game I was playing for about 2 months before it died. The computer was great, never overheated and easily ran all my games without a problem. I am at a complete loss. It was also not lightning because we haven't had any all week. Any possible suggestions would be greatly appreciated!

UPDATE: Considering that my PSU still shows that it is getting power with the green LED lit up, I believe it is something to do with my computer receiving the power. When I picked up my computer, I heard something falling around, a screw maybe? I'm not searching the inside of my computer for any problems but any help would be great! I think my PSU is fine but somewhere in the connection to the computer is what's wrong. :[