2 PSUs 1 Motherboard

bugeyewrx · 7 Sep 2011 at 13:54

Is there any reason that with a bit of rewiring I can't use two PSUs with one motherboard ? I want the second PSU to power backup drives but it would be good for it to switch on and off with the rest of the system .

Or to put it another way can I use the motherboard to switch a second PSU on and off ?

Nick1881 · 7 Sep 2011 at 14:00

Only way would be to wire an extra switch to the front of your case to switch the second PSU, it wouldn't need to be connected to your motherboard.

panyan · 7 Sep 2011 at 14:04

i saw this little device that connects from the molex of the main psu to the 24-pin of the secondary psu

the idea is that this circuit senses when the molex gets power (i.e. you've press the on button for the computer and main psu) and this starts up the secondary psu

bugeyewrx · 7 Sep 2011 at 14:06

So I can't splice the green and black wires from the second psu that I'd use for the switch into the atx connector of the first psu and switch them both from the mobo ?

Orcvader · 7 Sep 2011 at 14:06

If it's only for back up drives, and you want to control the power externally from your PC, then all you need to do is wire a switch to these pins on the 20/24 pin connector:

http://lib.store.yahoo.net/lib/directron/2psfig7large.jpg

EDIT: If you want the second PSU to turn on and off at the same time as the main PSU, then you can just wire it like so: http://www.frozencpu.com/images/products/main/cpa-167.jpg

bugeyewrx · 7 Sep 2011 at 14:14

I had thought of a second switch but as it's for a server / backup box that sits in the cellar it would be much easier if I could restart / reboot everything remotely from my main pc .

@ panyan ..... anymore info on that , sound just the thing

bugeyewrx · 7 Sep 2011 at 14:16

Orcvader ..... Thanks just what I was hoping would work