I built my first PC today but when I turn it on nothing happens. No fans, no beeps, nothing so I'll start from the beginning hopefully someone can help me out. Build: RAIDMAX SMILODON ATX-612WBP Black SECC STEEL ATX Mid Tower Computer Case 500W Power Supply - Retail GIGABYTE GA-P35-DS3L LGA 775 Intel P35 ATX All Solid Capacitor Intel Motherboard - Retail XFX PVT88PYDF4 GeForce 8800GT 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Retail Intel Core 2 Duo E8400 Wolfdale 3.0GHz LGA 775 65W Dual-Core Processor Model BX80570E8400 - Retail LITE-ON 20X DVD±R DVD Burner With 12X DVD-RAM Write Black SATA Model LH-20A1S - Retail (2) GIGABYTE GN-WP01GS PCI Wireless Adapter - Retail Seagate 120GB and 400 GB hardrives (used) 2GB memory 2x 1GB (bought to replace bad memory on another computer but turned out to be bad memory ports don't know brand etc.) I built it following online instructions and using my own previous knowledge of computers. It's not my first time inside one but my first time building from scratch. Assembly went well with no real problems. I used an antistatic wrist band clipped to the case. I completed assembly and flipped the power supply switch and the lights on the keyboard flashed (this is what confuses me most). I pressed the power button on the front and nothing happens. No fans, no beeps, no lights, absolutely nothing. I checked the front panel button connections and they're correct. I stripped it down to the mobo, PSU, and CPU. Same things happened. I tried shortcircuiting the PSU ATX power plug (green wire to black wire) leaving it connected to the fans. The drives were left disconnected from when I stripped it down. Again nothing happened and of course the keyboard lights didn't flash this time. This has lead me to believe that I have a bad PSU except the flashing keyboard lights confuse me. All parts were bought from newegg.com unless otherwise stated and are still eligible for replacement. So do I have a bad PSU? or a bad mobo or cpu? I believe it's safe to say it's one of those three but which I'm not sure. My personal opinion is that the CPU is least likely to be the problem. I could return any combination of the three for replacement. What are your opinions on the problem?