computer power supply for fans

RBroskie · #1 (**permalink**) 02-08-2007, 04:15 AM

can a computer power supply be used for fans so i dont have to rewire anything. im not trying to burn my house down because i screwed up a wiring job!

defaced · #2 (**permalink**) 02-08-2007, 04:29 AM

Yes. If it's an ATX power supply, you'll need to short two wires on the main power connector to get it to start. See the last part of this post for the details. http://dendroboard.com/phpBB2/viewto...20294&start=62

RBroskie · #3 (**permalink**) 02-08-2007, 05:46 AM

perfect! thanks defaced!

Arklier · #4 (**permalink**) 02-08-2007, 08:25 PM

An AT power supply might be your best bet. ATX PSUs only have a switch on the back of the box. This is because with an ATX PSU, the normal on/off function is controlled by the computer's motherboard. Even when the computer is off, some current still flows so the mobo can sense when the power switch on the case is pressed. The switch on the back is to physically cut the power for when you're working on the PC. AT PSUs are older, but they have a remote switch on a cord connected to the PSU (it was meant to be attached to the case). So if you got an AT PSU, you can attach the switch to your stand, or hide the main body of the PSU behind the tank.

RBroskie · #5 (**permalink**) 02-09-2007, 03:18 AM

thanks for the replies. arklier do you think you can plug the 60 -80mm computer fans right into the power supply or will any splicing need to be done?

Arklier · #6 (**permalink**) 02-09-2007, 05:29 AM

Most computer fans will have the necessary connectors, and those that don't will generally have an adapter. They're made to be plugged directly into the 4 pin molex connectors on the PSU.

defaced · #7 (**permalink**) 02-09-2007, 07:23 PM

Considering computer fans were intended to be used with computer power supplies, you shouldn't have any problem.

I use an AT supply for that very reason. Easier to set up.

RBroskie · #8 (**permalink**) 02-09-2007, 07:46 PM

defaced, how do you short the two wires you mentioned in your other reply?

defaced · #9 (**permalink**) 02-09-2007, 08:25 PM

Look in that post I linked to in my first reply, and follow the instructions there. I've never done it, but I know it works.

Arklier · #10 (**permalink**) 02-09-2007, 09:09 PM

If you don't feel confident in jumping it, you can buy a power supply tester that will turn on the PSU. That's how I run coolant through my water cooling case to get the air bubbles out when I change the fluid. They run about $5-$10 at the computer store or online.