Computer will not turn on....

[stuman19]

Just built a new system for my buddy, and when I hit the power button on the front of the case nothing happens. I have made sure that the Power Switch cord is properly plugged into his Chaintech Motherboard. Here are my thoughts as a possible problem.

He has a Viper case that says it supports both AMD and Intel and he has a Athlon 64. When I went to plug in that big fat power cable from the power supply that I always have in the past it was too short. I found this smaller (much smaller) cable that went into a four pronged port on the motherboard. Does his power supply only support intel boards? I think it has to be something to do with that one cord not being long enough to fit.


EDIT: Since I don't have a digital camera This will give you an idea of the connection that does NOT fit. This worries me. The one from the PSU is too small for the one on the board. Scroll down a bit to view the picture.


Thanks for reading,
Stu

 

[Cook1]

So did you connect the power cable and the 4-prong into his motherboard? Which one was too short now? I'm a bit confused.

 

[Farmer]

It would really help if you spelled out your exact system specs. If you have a P4 system and a pre-P4 PSU, chances are it does not have the AUX 4-pin power plug and you need that for the P4 system to run.

What you said about the power cable worries me. Unless you have a new modular PSU (in which case you shouldn't have the problem you are having), you can't simply "unplug" cables from your PSU. Please explain a bit, and provide photos if you can.

Assuming that's not the problem:

Since you've already checked all your connections:

1.) Make sure the risers you installed onto the backplate are in fact keeping your mobo entirely clear from the backplate.
2.) Check again; make ultra sure your 12V connection is attached completely. I recently did some cleaning and wasted 20 minutes because it wasnt properly connection

Unplug the cord from the button to the mobo, and tap those connection pins with a screwdrivers and see if that gets things spinning.

If all else fails, remove the mobo from the case, lay it ontop of the mobo retail box, install CPU, RAM and vid card, attach power cables and do a boot from there. And, from now on, on any new build, always do this before putting everything in the case.

 

[jaedaliu]

you need to attach both cables. As a test, you can remove the power supply from the case to make sure the computer works, but long-term you need a new power supply or find a way to extend that cable.

 

[stuman19]

Originally posted by: Cook1
So did you connect the power cable and the 4-prong into his motherboard? Which one was too short now? I'm a bit confused.

Yes, I connected the 4-prong cable to the motherboard. Its hard for me to explain but the longer white 24 pin (I think) port on the mobo is too big for the corresponding plug from his psu.

 

[stuman19]

Originally posted by: Farmer
It would really help if you spelled out your exact system specs. If you have a P4 system and a pre-P4 PSU, chances are it does not have the AUX 4-pin power plug and you need that for the P4 system to run.

What you said about the power cable worries me. Unless you have a new modular PSU (in which case you shouldn't have the problem you are having), you can't simply "unplug" cables from your PSU. Please explain a bit, and provide photos if you can.

Assuming that's not the problem:

Since you've already checked all your connections:

1.) Make sure the risers you installed onto the backplate are in fact keeping your mobo entirely clear from the backplate.
2.) Check again; make ultra sure your 12V connection is attached completely. I recently did some cleaning and wasted 20 minutes because it wasnt properly connection

Unplug the cord from the button to the mobo, and tap those connection pins with a screwdrivers and see if that gets things spinning.

If all else fails, remove the mobo from the case, lay it ontop of the mobo retail box, install CPU, RAM and vid card, attach power cables and do a boot from there. And, from now on, on any new build, always do this before putting everything in the case.

The motherboard is a Chaintech VNF4/Ultra and he has a Athlon 64 Socket 939. I know I used all the risers when installing the motheboard and I'm not sure what connection you nean by the 12 V.

 

[stuman19]

Originally posted by: jaedaliu
you need to attach both cables. As a test, you can remove the power supply from the case to make sure the computer works, but long-term you need a new power supply or find a way to extend that cable.

I can only attach one cable, the other one can only be forced into the mobo and has pins on the two sides. I know that can't be right.

 

[Kid Vicious]

amd64 cpus and motherboards require both a 20/24pin (fat) atx power cable and a 12v (4 prong) power cable plugged into the motherboard. plug in the 12v cable and the board and cpu should boot fine.


Edit: oop didn't see all the replies. nm.

 

[stuman19]

Originally posted by: Kid Vicious
amd64 cpus and motherboards require both a 20/24pin (fat) atx power cable and a 12v (4 prong) power cable plugged into the motherboard. plug in the 12v cable and the board and cpu should boot fine.


Edit: oop didn't see all the replies. nm.

It seems as if the cable from the PSU is 20 pin and the connector on the mobo is 24. They do not match. Need a different psu?

 

[Farmer]

stuman19:

Hmmm. A photo of your PSU with all of the connector layed out would really be helpful. Do you by any chance have access to a digital camera? You can hostem on Imageshack.us

 

[stuman19]

Originally posted by: Farmer
stuman19:

Hmmm. A photo of your PSU with all of the connector layed out would really be helpful. Do you by any chance have access to a digital camera? You can hostem on Imageshack.us

Let me see what I can dig up.....it will take me a whie to get a DIGI but I think it can be done. I will host once completed. May take me a while to get one though.

 

[jaedaliu]

Originally posted by: stuman19

Originally posted by: Kid Vicious
amd64 cpus and motherboards require both a 20/24pin (fat) atx power cable and a 12v (4 prong) power cable plugged into the motherboard. plug in the 12v cable and the board and cpu should boot fine.


Edit: oop didn't see all the replies. nm.

It seems as if the cable from the PSU is 20 pin and the connector on the mobo is 24. They do not match. Need a different psu?

don't really know if you need a different PSU, check

http://forums.anandtech.com/messageview...atid=27&threadid=1478987&enterthread=y

it's stickied at the top of the general hardware forum.

 

[bocamojo]

ATX standard is 20 pin, I believe. The mobo probably has both the 20 pin connector and the smaller 6 or 8 pin connector (12v). You would need to plug both of those in for your system to work properly. It sounds like the power supply has a 24 pin connector, which is too big for your motherboard. If that is the case, you will need to get a different power supply (one that has a 20 pin ATX connector), or a different mobo (one that will support the 24 pin connection).