PSU Query

[Tesla]

this is more of a curiosity...I was putting back together a pc earlier today, and noticed as i was putting it back together, the blue PSU cable had been snapped, i put the power into the M/Board and switched it on and everything still seems to work fine. anyone know what purpose that cable serves? i just always assumed if one cable broke that was it for the power supply...

[MordyT]

Picture of the connector? A blue cable in yours may not be blue in mind...

[Domino]

A blue cable in yours may not be blue in mind...

 

Woah, dude that's deep.

[Oaktech]

Well, this seems to suggest blue is a -12v... Which, as it's the only one, suggests it could be important!

 

[Tesla]

yeh, which is what has confused me. i can't lie i don't really understand it all (various voltages doing what), if a power supply does blow up (had two fail in the three and a bit years i've been a tech) i'd just order a new one....

[Joanne]

Maybe it powers part of the motherboard that you don't use... like PS2 ports, or suchlike.

[Oaktech]

My only thought is that this particular MB doesn't need a symetric 12v power supply, because it creates it's own from 1 of the +12v supplies or just doesn't use it.

[Tesla]

fair enough, like i said it's more a curiosity if anything, as i don't know much about psu's didnt know if anyone would have a more definitive answer

[Joanne]

haha... not my specialist subject

[Tesla]

the computer in question is still in bits.... so there may be something i find out later doesn't work. but i pressed the power and the light came on and things started spinning... haha.

[Chris_Cook]

From memory, -12v was only used for rs232 serial ports and maybe some really old disk drive controllers. Don't think it gets used for anything these days.

 

Best bet is to make sure it can't short on anything. I would recommend you replace the PSU unless you can do a decent repair on it.