I've just finished building a new PC for my brother. Only, when I turn on the power, it al looks promising for about a second, maybe two, until the power goes dead. It wont even try again until the powe has been turned off at the mains.
The power light on the mobo shows up fine, though.

Anyone have any ideas??

what are the system specs?

Oh, yeah, sorry.

AMD 3000+ (w/ Tt Volcano 9) - I'm not gonna overclock, you see. So I figured this would be sufficient.
512Mb Crosshair XMS PC3200
Samsung 160Gb SATA SpinPoint 80 HDD
COLORSit 400w PSU
ASUS Radeon 9600XT
ASUS A7V600 mobo
CD rw
DVD reader

If it seems to power up for a bit and then cutout it might be that the current draw is too high for the psu so it's cutting itself of as overload protection... if it was just shorting out, it should cut out right away instead of a few seconds....

my first guess would be that the psu is underpowered... but it's kinda hard to say without any system specs...

edit: that ISN'T all that matters if you're talking about power requirements of a 400W psu... like the graphics card? what is that? why not just list everything that uses electric...

lol, I was actually re-writing them as you posted, cos I realised that it all makes a difference

http://www.jscustompcs.com/power_supply/

have you got another psu to try instead? maybe something with a brand name?

is there a fan plugged into the CPU_fan header on the mobo? if not, it might be cutting out for thermal protection....


what I suggest, is to take it apart and start over...
or at least go through and check EVEY connection... don't just look at them, touch them and make sure they are OK..


is the floppy cable on upside down? (we ALL do this once in a while...)

Hmm...

Just keep digging...

yeah, I have the fan plugged into the cpu fan header.



It doesn't even have a floppy, yet

Hmmm...can you get into the BIOS?

Do you have a floppy around?



Not sure if this is it, but I had a system that wouldn't boot because the BIOS had the floppy controller enabled and I didn't have a floppy plugged in...
I plugged a floppy in change the BIOS and away it went...

if you have one around it might be worth a try...

Well I checked all the connections, and everything was Ok, still not working, but when I removed the CPU and put it back, it stayed on.

The only problem now, is that I get no picture on my monitor. I took out the card and tried it on my machine, and it works fine. I also tried my girlfriend's FX5600 in there, and that gave no output to the monitor either... But I guess this is info for the Video Cards Forum...

Hmmm...... are you sure the Mobo is good....or the CPU?

anyway you can swap things around?

Well when I had similar problems with my KT400A board it was cause my RAM and processor were at different FSB's and I noticed that you have a KT600 board so if you can try some PC2700 RAM in there since your processor has a FSB of 333.

Oh, I thought the 3000+ had a 400Mhz FSB... well, anyway it was the CPU. I posted a photo (in the CPU forum) of my processor when I removed it, and there was a crack right through one of the little rectanular bits (I forget what they're called ) So panic is over... Unless it could be the RAM... (obviously aswell as the broken CPU, cos the RAM cost me £100 (around $190US)