Help! Computer won't start!

I just finished building the computer found in my signature. I put it all together, triple checked all power connections, and checked the power on connection on my motherboard. I hooked everything up and hit the power switch. Nothing. No fans spun up and no noise. I have changed out the power cable itself to no avail. I went back and rechecked everything including checking if the power supply was set to the right voltage. The only sign of life i could find is that a light, in the socket for my ethernet cable, turned on and remained on till i turned off the power. I also heard a noise akin to that of a monitor turning off when i turned off the power. Please help! I have been waiting so long to get this system together and its very fustrating now to not even be able to turn it on. The power supply btw is an Antec TruePower 430.

well i just put a new psu in my puter and had the same problem i even had the led turn on that was on the mobo but nothing well what happend is i was off one pin on the floppy drive and it wouldnt let it turn on also i have had that problem when i dont have the cmos jumper in the right pos.

Jumper your PSU like this;



If the fan spins up, you'll know that the PSU isn't the problem. Then you'll have to start by reseating the CPU, RAM, and video card, one at a time, and hope all your components are OK. As was suggested above, make sure your CMOS is properly set and any other jumpers are set correctly.

yeah, do what stool said. Jumper your PSU like in that pic. If the fan in the PSU works, then the PSU is good.

I'd try this next---hook the PSU to the motherboard. Take out your RAM, CPU, EVERYTHING. Nothing but the motherboard and PSU in the case, hooked up to the switch in the case, and the system speaker in the case.

If it makes a bunch of beeps when you turn it on, then the mobo is *probably* good. You can look up the beep codes in the owner's manual if you want...but they are almost certainly just saying that you don't have RAM or CPU connected...which, of course, you don't.

Also, again, the PSU fans should spin. If absolutely nothing happens when you try JUST the PSU and the mobo...and you know the PSU works, then the mobo is almost certainly defective...or, you did something wrong, like stick the power connector in backwards.

If everything's working so far...add the CPU and heatsink (those go together, of course).

And that's the way to figure out your problem. Be systematic, add only ONE unknown to the equation at each step.

exact same thing happaned to me about 1 1/2 months ago. I cleared to CMOS, and it started fine, but that obviously isn't your problem.

Thanks for all the help so far. I am first going to make sure i didn't flip any connections like the atx power connection or the floppy like suggested above. Then i am going to rip everything out of the case and try and start on just the hard drive, the cpu, memory, board and power supply. Then if that still doesn't work i am going to go through piece by piece and try to determine what isn't working. Thanks again for all the help so far.

My computer doesn't boot if I happen to put the floppy power cable backwards in. Bloody thing goes either way, and the first time is always the wrong one.

Thx again for all the help. The culprit turned out to be the usb header, to which i had incorrectly connected the front usb ports. Again thx for all advice getting this setup. Btw here is my first 3dmark bench on this machine http://service.futuremark.com/compare?2k1=5528709. I'm really excited since its over twice what i was getting on my dell with the same vid card!