Just finished building my new computer and when I go to turn it on, everything flashes for a second (lights, fans) and then it stops, nothing else happens. This is a brand new build, and I went over the checklist of things that might be keeping it from booting. I took it all apart, re-did it all step by step straight out of the motherboard manual. The green LED on the motherboard is lit when plugged in, and when switched on in the first second all of the fans spin and the lights blink, and then nothing except the green LED on the motherboard.
ASUS M4A78T-E AM3 AMD 790GX HDMI ATX AMD Motherboard
AMD Phenom II X4 945 Deneb 3.0GHz Socket AM3 125W Quad-Core Processor Model HDX945FBGIBOX
Patriot Viper 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Dual Channel Kit Desktop Memory Model PVS34G1333LLKN
HIS H489F1GP Radeon HD 4890 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card
CORSAIR CMPSU-650TX 650W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC Compatible with Core i7
SAMSUNG Black 22X DVD Burner Black SATA Model SH-S223B
Antec 900 case
I've tried reconnecting everything, I've tried removing the ram and trying each on individually, and I've tried taking everything apart and looking at each part to make sure it wasn't bent/broken etc. I also used an anti-static wrist stap while building. The only thing I haven't done is plug in a system speaker, because I don't have one.
First, you need a system speaker. Right now, you do not know if the system is POSTing, but not booting; or if it is POSTing unsuccessfully; or if it not POSTing at all. Each of those three possibilities leads to a different troubleshooting path.
I got the speaker, but I can't figure out where it should plug into. I thought it went right above the HDD LED/PWR Reset plugs, but when I put it in there and turned the system on no sound came from it. So I figured either that's the wrong spot or the silence is the answer. If it is the wrong spot, then where does it go?
Checked the manual and I had the speaker in the right place. After that I went through and completely re-built it all again, this time using washers under all of the screws on the mobo, and still nothing happens when turned on except for the lights blinking and fans spin around once. Still no sound from the speaker. So is the problem the mobo?
Try removing the mobo from the case. Put it on a piece of cardboard next to the case. Plug in a single stick of RAM, the hard drive, CPU, PSU, and video card. Unplug everything else. Try booting like that.