Combining PSU's

[evil_genius]

Well I'm the latest victim of the crossfire current requirements. Tomorrow I'll be off to buy a Thermaltake Pure power 250 secondary PSU.

But while reading the various reviews of the thermaltake unit and a similar device. I have been thinking. If a second PSU can be used to power todays power hungry systems. Why can't I install any of the older PSU's I have lying around my place now? Anyone whose been into computers for more than say 5 years is bound to have a few extra PSU's collecting dust. I've got several old AT and ATX supplies here. Some of which claim to have fairly robust 12V rails inside.

There has to be some electrical reason no one is doing this yet(I honestly can't even find anyone talking about doing it). I'd just to know what that reason is.

[Mad-Max]

It's easy to do really, well it is for me, you just have to wire in the second psu to the first one so it switches on when the first one comes on.

But I would suspect that most people would say and do is buy a new psu, some thing like Corsair/Seasonic.

/I'll find you some links tomorrow.

[evil_genius]

I wait with baited breath.

[Mad-Max]

After a quick look on google I've found this

http://forums.bit-tech.net/showthread.php?t=108208

http://www.overclock.net/faqs/19851-...-together.html

http://pc-mod.com/articles/atx/

http://www.techspot.com/vb/all/windo...on-button.html

More results HERE

[evil_genius]

hmm. I guess I wasn't clear in my request.
I mean, not just using one PSU on the harddrive and another for the mainboard and the GFXcards.

I mean physically connecting all of the +12volt rails from both PSU's together. And then bridging the power buttons together.
(There is some really terrible advice in some of those links)
Confused Fishcake: What you REALLY don't want to do is power your GFX card and motherboard from separate PSUs.

He should tell that to Thermaltake and FSP.

I've found a link that talks about it. But the forum rules won't let me post it yet.
Check out the article named How to link multiple AT PSU's into one BIG PSU on procooling . com from 2001.
I'd love to fgind a version tha is updated for ATX psu's.

[IAmATeaf]

hmm. I guess I wasn't clear in my request.
I mean, not just using one PSU on the harddrive and another for the mainboard and the GFXcards.

I mean physically connecting all of the +12volt rails from both PSU's together. And then bridging the power buttons together.
(There is some really terrible advice in some of those links)
Confused Fishcake: What you REALLY don't want to do is power your GFX card and motherboard from separate PSUs.

He should tell that to Thermaltake and FSP.

I've found a link that talks about it. But the forum rules won't let me post it yet.
Check out the article named How to link multiple AT PSU's into one BIG PSU on procooling . com from 2001.
I'd love to fgind a version tha is updated for ATX psu's.

If the PSUs that you bridge together have PFC then connecting them together as above would most likely screw this up. You'd be much better bridging the power good and power buttons together so that both PSUs turn on via the case power button and stay powered and then use them to power bits of your system. You'd also need to common the earth or GND on the both PSUs else you could end up with fluctuations in the supplied power which again would cause havoc.