Why does this PC start up when I plug in the power supply?

[MichaelD]

This is puzzling the crap out of me. It's my server; I put a new HSF on it yesterday.

It uses an Abit KT7R mobo, and if you're familiar w/that board you'll know that the socket is turned 'the wrong way" and is right on the edge of the board. so the PS blocks access to the clip, necessitating removal of the mobo from the case in order to get at the CPU/HSF.

Removed the board, replaced HSF, reinstalled. When I plugged the power cable into the PS, the PC booted up. WTF? Tried it again. Same result. Thinking maybe I wired the case leads incorrectly, I cracked the case open for a peek. *shrug* Every thing looks fine.

The PC runs perfectly, shuts down perfectly and restarts perfectly...but if you remove the plug from the PS (while the PC is off, of course) and replug it, it fires up.

It didn't do this before. It's an older Antec 300W ps, if that helps. I'm puzzled.

 

[Adul]

have a look in bios and see if there is a setting related to that

 

[MichaelD]

Hmm. Didn't think about that. Come to think of it, I did clear the CMOS after reinstalling the board...it's just a habit I have that if I disconnect everything (which you have to do to get the board out of the case) that I reset the CMOS...it makes me feel safer that way.

I'm also using a later bios...maybe a power management setting is turned on by default or something...I'll have a look. Thank you.

 

[OS]

I think some BIOS have an "auto on upon power resume" option or something like that.

 

[MichaelD]

Originally posted by: OS
I think some BIOS have an "auto on upon power resume" option or something like that.

That rings a bell. Thanks guys, I'll check it out.