Ignoramus in search of help

[akujin]

Using Mechbgon's guide and lots of browsing here I am attempting to benchtest a comp as follows:

Asus A8V MB
9800pro vid card
OCZ 420watt power supply
1gb mushkin RAM
Athlon64 3000+ socket 939

Everything seems to be plugged in properly. When I turn on the power supply the fans turn briefly and the lights on the psu turn on briefly then stop. When I try and turn the power on to the computer I get nothing. Currently sitting on top of the box the MB came in. Any ideas?

 

[SrGuapo]

Are all the parts seated properly? RAM, video, CPU, heatsink? All the correct power connectors are plugged in? Any beep codes/80port readouts? Try taking everything apart and putting it back together.

 

[akujin]

Reseating everything now

 

[akujin]

Alright, reseated everything. The correct power connectors are plugged in and still can't power up. Lights and fans still turn on briefly when I turn PSU on and motherboard power light is on.

 

[ts3433]

Inspect CPU for bent pins and make sure the heatsink is making good contact. Triple-check your ATX12V and the molex going to the 9800 Pro (and make sure you can see no contacts whatsoever sticking out from the slot on this card). You can also try testing another PSU in that rig and testing the OCZ PSU by itself (there are two wires you can connect to make the fans spin up and such, or you can use a PSU tester of some sort).

See if any beep codes the board gives you mean anything.

 

[akujin]

I am not getting any beep codes at all. Also, what two wires do I connect to test the ocz psu?

 

[akujin]

So the mistake I made was plugging the 4 part of the 20+4 power connector to the 4pin 12v connector on the motherboard. The fans stay on now but I still cannot power up my system. Have I broken something by putting in the wrong power connector?

 

[ts3433]

Uh-oh. That may have done something bad (I'm not sure, but the voltage mismatches might have screwed something up). Do you have another PSU that you can use to test with that system?

 

[akujin]

I don't have another that will work with that system at the moment. The fan on the PSU and the video card both stay on now. The CPU fan doesnt power up at all. Also, the system power LED is on and unaffected by my hitting the power button.

 

[stevty2889]

motherboard may have been damaged when you plugged the wrong connector in to the 4pin 12v connector. The 4 pin connector for the 20+4 connector has voltage across 3 of the 4 pins, while the normal ATX 12v 4 pin connector only has voltage on 2 of the pins..

 

[mechBgon]

Originally posted by: stevty2889
motherboard may have been damaged when you plugged the wrong connector in to the 4pin 12v connector. The 4 pin connector for the 20+4 connector has voltage across 3 of the 4 pins, while the normal ATX 12v 4 pin connector only has voltage on 2 of the pins..

Additionally, the voltages are not the same. ATX12V has two 12V (yellow) and two ground (black). The extra four pins on a 24-pin PSU are 12V, 5V, 3V and ground. So my guess is that the error probably damaged the motherboard.