This is a new one for me. When I press the power switch on the front cover of a newly built machine, the chassis fan and the CPU heatsink fan both spin up for about 1 second, then the machine turns itself off. No beeps. These are the parts (all from Newegg.com) Antec LifeStyle SONATA II Piano Black Steel ATX Mid Tower Computer Case 450Watt SmartPower 2.0 Power Supply ASUS P5N-E SLI LGA 775 NVIDIA nForce 650i SLI ATX Intel Motherboard Intel Core 2 Duo E6600 Conroe 2.4GHz LGA 775 Processor Model BX80557E6600 EVGA 320-P2-N811-AR GeForce 8800GTS CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model TWIN2X2048-6400C4 Creative Sound Blaster X-Fi XtremeGamer 7.1 Channels PCI Interface Sound Card Seagate Barracuda 7200.10 320GB 7200 RPM SATA 3.0Gb/s Hard Drive Generic DVD/RW Drive What will typically cause a computer to shut itself off right away? Update: I did some trouble shooting exercices. 1. I took out everything except Mobo and RAM. no change 2. I tried the RAM in different DIMMs, no change 3. I took the mobo out of the case, set it to the side (not too far, the power cable doesn't reach), no change. My latest test connection set up is the mobo sitting next to the case with only the 24 pin power cable and the 2 pin power switch cable. Again, once I pressed 'power' all three fans (PSU, CPU, Chassis) spin for less than a second and then shut down. What is this?