Motherboard powers on by itself!!! Argh!

**kiztope** · 04-19-2006, 12:20 AM

Heres the deal, please help me if you can...
My setup is in my signature...
It just started doing this...

My motherboard will automatically power on when the ATX connector is connected to the motherboard. It does this regardless of whether it is connected to the opus, or an AC atx power supply. It will power on without using a jumper, or the opus green-white connector.

Also, when the computer finishes it's shutdown routine, it will shut down, but remains powered on... if you know what I mean.... The pc will be in a shutdown state, but the HD and the fans, etc will still be running.

What the heck is goin' on!

I really need some help with this, I have been plugging/unplugging my opus for the last couple of months just to use the carpc....

I checked the bios to see if the option to auto power-on the pc after a power failure was enabled... It isn't.

Any ideas?

**nkotch** · 04-19-2006, 12:29 AM

Using a known working normal ATX power supply, take off all components (HD, ram, USB devices, etc...) and start from scratch. With everything off plug in the power supply and see if it still does it and/or if you get warning beeps (from having no ram in, etc...) then disconnect power, add in another component and reconnect power, repeat..... See if maybe a device is messing with it somehow. This is basic, but also make sure nothing is obviously shorted on the board (looks like you tested it with nothing connected to the power/reset pins...)

**Specimen** · 04-19-2006, 12:58 AM

I've seen this happen to someone who's computer I had to fix. Their problem was that they plugged in everything into their motherboard FPanel wrong. LOL, they had the HDD LED plugged into where the PWR SWITCH goes so the motherboard was always powering on the second the ATX power was connected. Double check all your connections on those pins. That might not be the case, but check to make sure you're not shoring the pwr on pins.

**AllThingsEnd** · 04-19-2006, 03:06 AM

ive seen this happen too. make sure those connectors are in the right spots.

**kiztope** · 04-19-2006, 08:27 AM

@ nKotch - I'll try all that tonight...
@ Specimen - Thanks for the advice! I've seen people do the same thing!!! However, I don't have anything connected to the front panel header.
Before I made the first post, I also double checked all the other jumpers (Audio, reset cmos, etc). Everything else looks fine....

**kiztope** · 04-19-2006, 01:42 PM

Well, I tested it...
Even with nothing but the power attached, it still powers on
Any other ideas?

**Specimen** · 04-19-2006, 09:21 PM

There might be something in the Bios that is starting it up in the Power Management Settings. Change the ACPI Function from Enable to Disabled and see if that helps. If not, try clearing the Bios by jumping Pin 2-3 on the JP1 pins (Clear CMOS) near the CMOS battery. Just incase there is something in the Bios that’s gone crazy. Do this with no power connected to the motherboard. Make sure you have this set back to jumping pin 1-2 when you are done. If this doesn't clear you problems then there is a hardware problem or some pins are being jumped when it shouldn't be, or something is being shorted.

Since this is an older board, check to make sure the CMOS battery isn't dead also.

**kiztope** · 04-19-2006, 10:55 PM

Well, I already tried clearing the cmos.... no change.
My bios doesn't allow me to change the Acpi functions....

Any other ideas?
Is my mobo toast? Why would this be?

**2k1Toaster** · 04-20-2006, 12:16 AM

Could be the power on after power failure is set to "ON" in BIOS. Also could be the green ATX cord is grounding itself somehow turning it on. I don't know how though...