Computer does not start for more than 1 second

I connected all the wires to the mainboard and everything else. I installed the CPU, ram and hard disks. When I go to turn it on it just starts for like 1 second and turns off again.
The mainboard LED is on and the fans actually spin a little. And that only if I don't have the CPU power connector plugged in. When it's plugged in it just gets a tiny impulse that causes the CPU fan to shake somehow.

Now I tried to unplug everything but one ram stick and the CPU, but it didn't help. I guess it could be the mainboard or CPU. PSU can't be it since I tried like 3 different ones, same for Ram, harddisk and stuff...
I just bought all that stuff, it was originally packaged and hasn't been used before.

Well I could really need some help if any of you got Ideas.

Here's my System:

P4 3E Ghz (Prescott)
Asus p4c800 deluxe
2x 512 ddr400 ram
one hard disk and a DVD


It's like the power runs through the system for a sec. and then just dies...

um... hmm.. ive heard the prescott has a certain power requirement... are you sure your asus is prescott compatible. I have a mb that would be prescott ready if i upgraded and flashed my bios... but i dont want to mess with it.. anyway check your manual to check for prescott compatibility... and keep in mind that just because it doesnt say its not compatible doesnt mean it is.... IE (make sure it says prescott ready)

yepp, It is prescott ready and supports everything else I have in it.

I had an issue with this one time. Make sure the wire that goes from the case power button to the motherboard(to tell it to turn on) is snapped on all the way. That should be the first step. My computer did that because it wasn't down all the way.

I've been through all this basic stuff like 50 million times.
I just don't get what's actually broke or what I did wrong.
There's got to be something else, maybe the jumpers.I don't know

As a last ditch attempt you may need to think about paying $100 to CompUSA so they can fix it. That way you wouldn't need to worry about it and they would fix it within 10 days.

this may seem quite obvious, but check to make sure the fan on the heatsink is blowing air down. i built a computer for a friend once, and the fan on the heatsink came to us with the fan on upside down!! the exact situation you're describing here was happening to us.

did you clear CMOS after everythign was installed??? i installed new ram and i had this same issue. cleared CMOS and drained capacitors from PSU. turned it back on..and obviously it works lol. possibly your PSU is not functioning. it migth ahve a short in the wire to your motherboard. check that. hope that helps.

I had this exact same problem when I built my computer. Make sure your power on calbe and reset cable isn't switched. The problem is in power cables. I think the board manufacturer got the chart messed up, becasue I just had to mess around with the power cables, and it finally started up. I can almost guarantee that the problem is how you have connected the power, reset, suspend, and ground cables on the mobo.

Also, the CPU fan should blow the air out. The heatsink sucks the heat up from the processor, and then the fan sucks the heat off of the heatsink. If you had the fan blowing the air onto the processor, it would just be blowing down hot air.

Not to sound rude... but would the motherboard fry if you got the powercables or reset buttons got mixed up
Thats what my friend who taugh me about computers told me

elektrotek1 said:

Also, the CPU fan should blow the air out. The heatsink sucks the heat up from the processor, and then the fan sucks the heat off of the heatsink. If you had the fan blowing the air onto the processor, it would just be blowing down hot air.

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haha, whoops!!! meant to say up.

but would the motherboard fry if you got the powercables or reset buttons got mixed up

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If i understand you correectly... no. It just means the buttons on your case are misarranged.

Also, the CPU fan should blow the air out. The heatsink sucks the heat up from the processor, and then the fan sucks the heat off of the heatsink

Click to expand...

Actually a couple of ultra high performance heatsinks benifit from sucking the air away from the heatsink rather than blowing air towards the heatsink ... course by far and large you are correct