computer fans turn on and off every two seconds

[sef24]

so ive been trying to build my computer today and i unhooked the sata cables from the hard drive and dvd/cd drive. my motherboard lights turn on and stay on when i flip the power supply switch and the fans start going when i hit the motherboard power but then turn on and off every 2-4 seconds. whats going on?

also the front panel wires for the power/led/etc is very confusing and not sure where to hook them. i see a color coded pin slot on the motherboard which i plugged the small two slot led cable and it works though no idea about the rest.

also, i got the power button working i believe, though i notice whenever everything turns off for a moment, a small red light turns on from the motherboard near where i have the video card put in.

 

[foothead]

Check your manual for the headers.

As far as the fan, which one is it, and what is it plugged into?

 

[sef24]

well its the whole computer, i dont think the power supply is powering up except for a moment, it doesnt make the regular "sound" of the air and fan going though.

although once in awhile it does for a second and then powers down.

the s0/s1/s2/s3/s4 led light on the motherboard is going from s4 when on down to s0 when off, which is the light then changes whenever its on for the moment of powered off like usual

edit: actually its the s0-s5 without the word led in it

 

[foothead]

Okay, unplug the PSU from everything, take a paperclip, straighten it, then bend in half. Use the paperclip to jump green to black on the psu (in the 20 pin ATX plug), and leave it there. If the PSU shuts off after 2 seconds, its dead. If it stays going, its the motherboard.

Forgot to ask, what PSU is this?

 

[sef24]

no chance that it is the power supply? the comp just wont keep power for two seconds? i use the intel i5 core

 

[foothead]

It could very well be. Do what I just posted to test the PSU.

 

[sef24]

i really dont have any idea on what you mean to bend it and jump green to black

 

[foothead]

Bend a paperclip and use it to jump the green wire to the black wire on the 20 pin ATX plug.

14 to 15.

 

[sef24]

well i seem to not of had the 2nd power supply connected to the motherboard. which was on the top left when its mounted. it now stays on for 10-15 seconds but does the same. so yea it is an improvement but the same thing as before. does that help anyway on what another possible problem it is?

 

[foothead]

Unplug the PSU from the motherboard and test it before you do anything else. A bad PSU can easily kill your motherboard.

You still never gave a model number or wattage for this PSU.