mother board problem

[insane]

ok im building a computer for an uncle of mine in mexico but it wont power up i have checked all the conection 3 times and then checked the mannual but i get the same problem it powers for a few cpu fan spins for 3 seconds and then the computer shuts down it does not power up at all the fan spins and that is it i can see power but it does not start
im asking you guys for some help so lay it on me

o and the computer i have is the same spc's as this on

i got a matsonic ms9307c series mainboard sis 645DX chipset pentium 4 mainboard

with a pentium 4 celeron CPU 1.8 GHZ

1x 512 DRR  

radion 9200

400 watt power

and a 40 gb hard drive segate

[jscott3201]

2 things I can think of:

1) U put connector for pwr switch in wrong
2) Ur PSU is overloaded or not switched on in the back

[GX1_Man]

And these are all new components? You don't even get to POST? Are there any beeps?

Have you ever assembled a computer before? Have you tried removing and reseating everything?

I guess you could try to swap out one component at a time with known good ones. Have you stripped it down to motherboard, CPU, smallest stick of appropriate RAM, generic PCI video card and floppy?