This morning I connected an ethernet cable to the back of my computer, all the sudden the computer shut down with no warning (not in a shut down process, but as in all the sudden I heard the fans stop working and it was off). I thought to myself, no worries, maybe the power at my house went out, it didn't. I tried turning the computer back on and it goes on for maybe one second if even, then it shuts down automatically. I checked if it was the power supply cable by connecting it to another computer, it wasn't the other computer turns on just fine. I waited a few minutes and tried again, the computer turns on for about a second and it all shuts down with no warning after one or two second maximum. When I turn it on it doesn't make any beeps, no warnings, nothing, it just goes on, then shuts down. The computer is only two weeks old, please help me fix it.
Hard Drive: Western Digital Caviar Black WD5001AALS 500GB 7200 RPM 32MB Cache SATA
Video Card: XFX HD-487A-ZHFC Radeon HD 4870 1GB
PSU: OCZ ModXStream Pro OCZ600MXSP 600W
Memory: OCZ XMP Ready Series 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600
Motherboard: EVGA E758-TR 3-Way SLI (x16/x16/x8) LGA 1366 Intel X58 ATX Intel Motherboard
Processor: Intel Core i7 920 Nehalem 2.66GHz 4 x 256KB L2 Cache 8MB L3 Cache LGA 1366