HELP!! Case Grounding Problem (I Think!)

[alexmack]

I just bought a new OEM Compaq case from Directron - When I plug in the atx power connector to whatever motherboard I try, the power goes on right away without me having to push the power button.

I have built hundreds of machines over the past several years but I am stumped on this
one. When I try to install either of two good, know working motherboards with good, known working sdram - I can get the machine to boot from the installed floppy drive but as soon as I try to connect a good, known working ide hard drive, the power light on the front of the machine fails to light and, although the power supply turns on, I get no video and the machine fails to boot up.

I have tried several different hard drives and cable and am stumped. I am probably doing something stupid here but I am lost. Any ideas?

 

[randomboy]

Tried another PSU yet?

 

[alexmack]

Don't have another to try. I know the components I used are all good though

 

[randomboy]

I guess one thing to ask (probably things you've thought of), how big of a PSU wattage wise, which HDD, which mobo, what video card, what cpu?

 

[lenjack]

Check bios options.

 

[alexmack]

The thing is - the same motherboard(s) worked fine in an old H-P Pavilion case and an old Systemax case without me doing anything to the BIOS(s).
Could the ps be bad? The specs say it is P4-ready (and, of course, backwards
compatible"

 

[Bluefront]

You have a power supply problem. Just buy one at Best Buy....take it back if it doesn't fix the problem. But it will.

 

[stardust]

Basic fix. Did you reverse the Power Button plug in ur motherboard? That power button that connects from your case's power button to a select pin on your motherboard. You should see a little plus sign in the front of that pin and that should point to the back of the motherboard i think.

 

[alexmack]

Yep - tried the power switch cable both ways - same result

 

[Bluefront]

The power switch wire can connect to the board either way.....doesn't matter. Now if you connect that wire to the wrong pins, who knows? What if that power switch itself was bad?
You'll need a VOM to check it. Still think it's the PSU itself.

 

[randomboy]

All the power button does it short the 2 pins. If you really wanted to, you could start your PC with a screwdriver. If the switch was bad, the pc wouldnt even begin to boot. So rule that out. Get a new PSU, it seems to be the center of your problem :|

 

[alexmack]

Thanks for the tips guys - I'm getting a new ps from Directron

 

[Bluefront]

Well randomboy, if the power switch on the case were shorted (like pushed on all the time), The computer would start the instant the power cord was plugged into the ac. After that, any number of things could happen......