No Boot-Gigabyte Mobo

[lwnexgen2]

I just built a system for my parents,

1 GB Corsair DDR2 Value Select
Pentium 4 506
Gigabyte GA-81945PL-G
eVga 7300GS
Rosewill 350W PSU

Everything works fine on it, except when turning on after power is completely shut off, it won't boot. All fans turn on, mobo light is on, HDD goes on, CD Drives spin up, etc, etc, except nothing shows up on the monitor.

Turning off the switch in back and then starting allows it to boot again.

I have it using the 20 pin ATX power connector on the 24 pin port on the mobo, which Gigabyte says will work. I've tried booting with a 20-24 Pin adapter but no go, the heatsink won't even turn on and the PC shuts off after a few seconds.
I would really appreciate any help you could give me, I really have no idea what the heck is going on.

Thanks

 

[bman212121]

You may be pushing it on the psu a little bit. A 350 should be enough, but I'm not sure what kind of quality a rosewill has. When your computer boots up, all the parts turn on at the same time, which draws a lot of power. It sounds like your pc isn't posting (hear the beep when it boots) which means that something isn't working right before it is even up and running. You could try this... Turn off the pc by holding down the power button, then see if you can turn it back on. If it doesn't work, try pulling off hd's, opticals, etc, and see if it works then.

It could be due to something completely different, but if it is spotty with even turning on, it usually means that either the cpu / ram / mobo or gfx card isn't happy. That's all it takes to get the pc to beep.

Here is another idea, if you turn the pc on at it doesn't beep, (nothing shows on monitor, but everything sounds okay) try hitting the reset button. A lot of times the computer will beep and boot up just fine. When you overclock you can have that happen if your cpu is set too high for it to start up your computer.