New build wont turn on.

[cdub05]

Hi all, I'm building a computer for the first time. Everything is hooked up but it wont turn on . When I press the on button the LED on the case will flash for like a millisecond then nothing else will happen. And the power light is lit up on my motherboard so i know it and my power supply is workin. What am I doing wrong?


Here are my parts
Asus M4A78 Pro Motherboard
AMD Phenom 9850 2.5GHz quad core
BFG Tech 450W Power Supply
Creative soundBlaster sound card
Geforce 9800 GT graphics card

Any help would be greatly appreciated

 

[Abyssalx]

And the power light is lit up on my motherboard so i know it and my power supply is workin.

It still could be the PSU. the same thing happened to my first computer and I replaced my psu and it worked great. Even the fans turned on but it wouldnt run anything else. But I'm not saying go buy a new power supply.

Check all your plugs, maybe the power button isn't correctly connected? Maybe it's the motherboard. just because the lights flash doesnt mean that it's working.

 

[cdub05]

It still could be the PSU. the same thing happened to my first computer and I replaced my psu and it worked great. Even the fans turned on but it wouldnt run anything else. But I'm not saying go buy a new power supply.

Check all your plugs, maybe the power button isn't correctly connected? Maybe it's the motherboard. just because the lights flash doesnt mean that it's working.

Well the light on the motherboard stays on, so thats why im thinkin that there is power going to it. The led on the case is the one that just flashes and turns off. Ill check all connections again though. Thanks for the reply

 

[cdub05]

Ok, unpluged the power connector going to my graphics card. Its still doing the same thing except it gives a little beep and then turns right back off.

 

[shortstuff_mt]

I'd go through this checklist:

http://www.tomshardware.com/forum/261145-31-build-post-checklist

 

[jsc]

And the power light is lit up on my motherboard so i know it and my power supply is workin.

Unfortunately, no, you don't know the PSU is working. Every computer PSU has a small, independent, auxilliarly power supply called "STANDBY POWER" that is always on if the PSU is plugged into the wall. That is what is powering the LED even when the main part of the PSU is off (and if the main part is defective).

Go through the checklist:
http://www.tomshardware.com/forum/261145-31-build-post-checklist

then try this:

Pull everything except the CPU and HSF. Boot. You should hear a series of long single beeps indicating memory problems. Silence here indicates, in probable order, a bad PSU, motherboard, or CPU - or a bad installation where something is shorting and shutting down the PSU.

To eliminate the possiblility of a bad installation where something is shorting and shutting down the PSU, you will need to pull the motherboard out of the case and reassemble the components on an insulated surface. This is called "breadboarding" - from the 1920's homebrew radio days. I always breadboard a new or recycled build. It lets me test components before I go through the trouble of installing them in a case.

If you get the long beeps, add a stick of RAM. Boot. The beep pattern should change to one long and two or three short beeps. Silence indicates that the RAM is shorting out the PSU. Long single beeps indicates that the BIOS does not recognize the presence of the RAM.

If you get the one long and two or three short beeps, test the rest of the RAM. If good, install the video card and any needed power cables and plug in the monitor. If the video card is good, the system should successfully POST (one short beep, usually) and you will see the boot screen and messages.

Note - an inadequate PSU will cause a failure here or any step later.
Note - you do not need drives or a keyboard to get this far.

If you successfully POST, start plugging in the rest of the components, one at a time.

 

[cdub05]

Ah I see. Ill try these and get back to you. Thanks

 

[cdub05]

OK the heat sink fan is turning on, and its the only thing I have plugged up. When I did that, like I said it turned on but I got one long continuous beep that wouldnt stop until I turned off the PSU. I tried installing each one of my RAM sticks into each different RAM slot and still got the same long continuous beep.

 

[cdub05]

OK, I figured it out. Its definitely the power supply. Decided to hookup a spare PSU that I forgot I had, and everything worked just fine. thanks for the help