Please Help! PC doesn't power up

[gopalgk]

Hello all,
I built a new PC today and can't get it to power up. After several experiments this is what I could figure out. I place only CPU and Ram on the motherboard just to eliminate simplify things.

1. When I connect both the 20-pin and 4-pin power connector to the motherboard, as soon as I press the power button, the power led flashes once and the pc is dead.

2. When I connect only the 20-pin connector, the power led continues to glow after I press the power button. But since there is no power supply to CPU, the system won't go any further in boot process.

Why does connecting the 4-pin connector power down the system(The green led on the motherboard will still be glowing but all the fans stop immediately)?

Configuration:
P4 3.2GHz
ASUS P4C800 Deluxe
1GB PC3200 DDR 400MHz memory
PSU 350W

 

[foreverxyoung]

hi,
yeah i had the saem problem 2. Make shure the ram is in right .. I dunno how that could affect it buht thats how it worked on mine. Make shure u find the cable labeled PWR Switch and plug it in horizontily on your motherboard.

 

[Nubius]

That 4pin plug just takes strain off the +12v rail. I've actually accidentally turned my computer on without it plugged in and it still started up.

Also make sure that your board doesn't infact require a 24 pin plug and not the 20 inwhich you'd need to get a 20 to 24 pin adapter.

Besides that either the mobo or CPU is dead I'd guess.