Twin PSU's

unklerosco

Anyone running twin PSUs???

I need to power my

Mobo
3 hds
2 dvd
9800
WC
two Uv tubes
Fan controler
4 fans


The fan controler needs two power inputs which sucks... Have two psus. My main one is a zalman n the other is a crapy 300w I got with a case but I might mod it with a papst 120mm fan n use it to power my fans/lights/watercooling etc.

What u think???

duridian

Could work if you have a Dremel and a suitably large case. You could use the 12V output of the main (presumably the Zalman) PSU with a relay from a car to switch on the second PSU by its mobo connector, so that both come on and go off virtually simultaneously. A normal 4 or 5 pin relay should be easy to wire up with spade connectors.
Are you sure that you really need that much oomph though? Those Zalmans are pretty beefy as PSUs go, it might have enough on its own.

unklerosco

Its easier to just splice the green n ground on the mobo connectors to turn them on n off together...

Thinkin I might make up some sort of molex cable to run down the side of the case n supply the lights n crap from the one molex connector from the psu.

Fleetwodcomputers.co.uk seem to have everything u need n they'll do it for u too.

duridian

Er... I wouldn't recommend splicing if by that you mean connecting the green wires from both PSUs mobo connectors together in an attempt to get the mobo switching both on... that could be bad... very very bad for your equipment. The trick with the relay is simple,cheap and won't short anything out. 12V from PSU 1 flows thru relay making the relay contacts switch and connect green of PSU 2 to ground thereby powering on PSU 2 safely without any connection between PSU 2 and the motherboard.

unklerosco

Gonna see if i can do with the one psu, from what ive researched allot of people just connect the two wires, obviously by using the proper means...

duridian

Connecting the green wire to a ground is the correct way to switch on the psu without a mobo, but I'd be very cautious about putting the two green signal wires together and connecting that to the motherboard in case of something happening. I'm not trying to do the b*ll*cks and put you off this dual psu idea, just I know you have had some bad luck with your motherboard and building plans lately and don't wanna see you run into more trouble if it can be avoided. The only mod with 2 PSUs I have seen online (not that I come across it that often ) seemed to use the relay approach.

unklerosco

http://forum.pcstats.com/showthread.php?t=24533&page=1&pp=10

Thats where i got the wire thing from, u got any links for that relay idea??? Better safe than sorry

Col_Loki

Mobo
3 hds
2 dvd
9800
WC
two Uv tubes
Fan controler
4 fans

LOL , 2 PSU's for that are you joking?

Grap one decent PSU and it will power that without any problems at all at all. If you want to be sure pop in an Antec 480w TP , or 400w Fortron ....... or mabye more if you want.

The 480w TP powered, 4 HD's, 2 DVD, WC, Xp2500@ 2480mhz, cathodes, fans, 9700pro, mobo, without a problem for me. There is no way you need more power than that.

Have you tried the 300w Zalman? They produce quite a bit more than there rated for. Im running spec in sig on a 380w Antec TP with minimal stress, and have run pretty much the same on a 300w Fortron.

hostyle

I've a 360W Chieftec PSU powering more (or similar) than that:

Mobo (w 3 PCI cards) / AMD proc
4 hds
2 dvd/cd
mid-range video card
zip disk (in use quite a lot)
two Uv tubes
Fan controler
5 fans
various USB-powered usb devices

Seeing as you have a hungrier video card and WC, get a slightlier beefier PSU and you should be fine. Sounds like work and possible problems with 2 PSUs - though it would be slightly cool

unklerosco

The cool factor is always looming

The zalman can power it, i just need alot more molex connections + I figure i could get a better overclock by stressing the Zalman less.

duridian

I managed to dig up the site that I got the relay trick from:

http://www.speedy3d.com/articles/case_mod_p3/index.shtml

He shows the relay thing on page 3 of the article. Page 4 is about the splice method. Now that I've re-read it I remember why the author of that article favoured the relay over the splice method and I think it is a very valid point. By splicing you are making the mod more permanent as it involves cutting wires of your psu's connectors, this means that if you ever want to resell your psu at a later time you are selling it with insulation tape or some such on the connector wires which frankly is tatty and certainly would make it less desirable for the prospective buyer. That Zalman of yours is probably worth a good few bob and who knows maybe you will want to sell it again next year. The end decision is yours but I think the relay is the better method.

leeroybrown

i just need alot more molex connections

You should be able to pick up some Molex Y-Splitters reasonably cheaply.

unklerosco

Thats a good point Duridian... Eever thought how it'd effect the resale of the psu. If i go ahead with twin psu's i'll put up a post wiv some picks.

Thanks for that link, that relay is allot easier than I thought.

duridian

You're welcome, good luck with the mod if you do go with twin psus

unklerosco

Im gonna go for it, seems easy enough and i aint afraid to try somfin new... The second psu is only gonna power fans, lights, wc etc. The Zalman is for the mobo, drives etc. Will post some pics when I get around to doin it...

That link is a great help, thnks again.

unklerosco

Started setting up my twin psu's, waitning from my dad to get back with some spade connectors to connect to the relay, thought id post these pics in the mean time...


Pos + Gnd from an unused floppy connector used to switch the relay on...

unklerosco

relay attached to case + pos n gnd from case

unklerosco

PSU 2 connections for relay

unklerosco

Finished, dead easy to setup... I'll be placing the second psu outside the case, could put it inside but there'd be cables everywhere n it'll be cooler therefore quiter outside.

Pic of the relay wired up...

duridian

Good to see it worked out for you.

unkel

unklerosco, you're mad. A decent 300W PSU like your Zalman (or is yours a 400W?) would have done the job. Or were you looking for an interesting little project for something to do

Originally posted by Col_Loki
Xp2000+ @ 2505mhz

Bejaysis Loki, did you have to prove an AMD can get a 50% overclock as well

(me bows)

unklerosco

My zalman could prob have handled it no probs, just got bored on a grey sunday afternoon. Sure it cost me nuffin, had a second psu lyin there n I got the relay etc free...

At least the power goin to my 9800pro n p4 will be stable n sufficient... Mind u these X800's sound tasty. First have to get my mobo fixed then i can dream