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Your power supply to weak to power all those extra fans? Do this...

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Feb 24, 2001
If you have an old AT powersupply laying around collecting dust. Unhook all of your fans except cpu as most motherborads require that you have it drawing juice from the board. But anyway hookup all the case fans and any others to the AT powersupply and just turn on the AT powersupply as they have thier own switch. And walah you have just taken the stress off of your main power supply.

I did this because if I had to many fans in on my board or just to many cards plugged in my pc wouldnt post and I have a 300watt power supply, but now a 230 watt powersupply runs the fans.

BTW thi sis just an idea.
I have this already but I hate reaching to the back of my box to turn it on.
I have another ATX PS collecting dust but was to lazy to do the dual PS mod, much easier turn them both on by the click of one button.
This seems like a great idea... I happen to have an extra AT PSU laying around and I was going to scrap the fan out of it, but I was thinking of buying a server case where you can have more than 1 PSU... My question is whether its possible to have them both turn on at same time with one switch/button like you said above... I would imagine server cases have this feature available, right? Also, that would be two PSU fans blowing air out - kill two birds with one stone!
You have to reach to the back of your box?

Guess thats why I have both of my powersupplys laying on top of my open case hehe. Plus the AT power supply im using has a switch that is a on teh end of a black wire that runs to the box of the powersupply. So I can mount the thing anywhere but since it hangs over the side if the case I have no problem with. Man I need to get pictures of my setup lol...Ive got wires going everywhere. Guess that what i get for modding an AT case. hehe-
another way is to use a "wall wart" transformer. The kind for your answering machine or whatever. They are pretty low current but can handle a couple 120's anyways
U can power on the AT psu together with the ATX psu by using a relay. Get a 12vdc relay. I connected the relay to the 12v line of my ATX psu to the AT psu switch. There are a lot of articles on how to hook up 2 ATX psu. Also,I quote this from one of the articles on the main page under "powering peltiers"

NOTE: If you use stand-alone AT or ATX power supply to power a tec, it will not put out 12 volts unless you place a 1 amp load on the 5 volt output.

From what I see on my DD5, I get abt 10.2V from my 12v line of the AT psu