Homebuilt PC issues, need help!

[Travenous0397]

I just recently put together a new budget PC and am currently having trouble getting it to POST. When it gets powered on all of the fans on the motherboard and in the case turn on, the DVD-RW drive light comes on and stays on, and thats it, a blank screen, nothing! The after POST beep never happens and the power button will not shut the rig off, it has to be done on the kill switch in back. I sent back the motherboard and they supposedly replaced it with a new one, but I have the exact same problem with the replacement.

MB: ASUS A8N5X (nforce 4, socket 939)
PSU: Antect 350W smartpower
CPU: Athlon 64 3000+
RAM: 2x Corsair DDR400 512MB
Video Card: ASUS 7300 GS

I haven't done too many 939 setups and noticed that the power connector for the motherboard from the PSU is missing a metal contact in the 5th pin down on the left side (the flat side) and am not sure if this is normal. I looked at a wiring diagram for this online and it is supposed to be a COM, but I would still think it needed a metal contact on the inside to be a COM.

Any help here would be appreciated as I am at a loss for what to do next!

Thanks.

 

[PrivateDonut]

Check and make sure the power supply is set to 115, there should be a switch on it. If it is set to 230 that would cause similar symptoms to what you described.

 

[Travenous0397]

I checked, and it is indeed on 115. Heh, I was going to feel pretty stupid if that was the case! Good suggestion though, thank you.

 

[smeghead4269]

That missing wire you mentioned is the -5V line, which this board (and most boards nowadays) shouldn't need. So that's not a problem.

I'd say your next step should be to try powering on the system with only PSU, motherboard, and CPU. No RAM, no expansion cards, no drives. Obviously it can't POST in this state, but if those three components are working properly it should give you an error beep when the board fails to find any RAM.

 

[Herr_Fritz]

Is the 4 pin power connected as well?

 

[The_OGS]

Is the 4 pin power connected as well?

LoL, excellent question (there I go, assuming again...)
And I will of course mention that your case must be properly configured for the exact bolt-pattern of your motherboard - if there is even 1 extra stand-off (which has no corresponding mounting screw) this is exactly what can happen...
Check for this and other shorts/misconfiguration including jumpers.
That powersupply sucks - but it was working okay before, right?
Hope this helps,
Regards

 

[Travenous0397]

Is the 4 pin power connected as well?

And now I'm going to hang my head in shame as this indeed was the problem. . . wow i'm a moron. This is far from my first homemade rig which makes it even worse. It's so easy to jump to the more complicated solution. Never underestimate the power of your own stupidity.

 

[Herr_Fritz]

Don't feel too much shame. Way too many people have done similar things.

The number one rule that you learn when building rigs (either through trial and error, or teachings from more experienced builders) is to read all the documentation for all of your parts, preferably twice, before ever touching any of the hardware.

Saves a lot of time and effort on the backside, when you finally get to power everything up.

Hope the rest of this build goes smoothly.

Fritz