How do I power 80mm fans from PSU?

**gold007eye** · 03-22-2006, 09:52 AM

I am thinking of building a custom "box" to house my Aopen Mini PC and other components I will be using. What I want to do is install 4 - 80mm x 80mm fans into the box to allow for ventillation and heat dissipation. The idea is good, my only problem is how can I power them? If I were to take a normal PC PSU and just plug it into a power source; will it power the fans (using molex connecters from PSU) or does the PSU have to be connected to a motherboard to power on? If you could help it would be greatly appreciated.

**tbird2340** · 03-22-2006, 10:06 AM

Is this for car use? If that's the case how would you plug in a normal PC PSU?

To answer your question.. Most 80mm fans require 12V which a PC PSU provides.

**gold007eye** · 03-22-2006, 10:08 AM

Yes, This will be for car use.

I guess that is my other question. Can you power a PC PSU without it being connected to a motherboard? Example: plug into an inverter?

**tbird2340** · 03-22-2006, 10:13 AM

You could yes.. But why would you want to do this? What are you going to use to power your carputer?

**gold007eye** · 03-22-2006, 10:19 AM

I am going to use a Carnetix P1900 to power the Carputer. (just have to figure out how to wire it to the ignition, etc.) The reason I want to do that is to power the 4 Fans that I want to put inside the box to keep the box cool and vetilated.

**tbird2340** · 03-22-2006, 10:35 AM

Hmmm. The Carnetix I used was strictly for startup / shutdown.. You sure you don't have to plug the carnetix into an actual PSU?

**InHoc** · 03-22-2006, 10:41 AM

Carnetix P1900 is a DC-DC PSU, that also has an on-board Startup/Shutdown controller. As for the fans, you can probably run them to the 12v line that the P1900 offers (probably going to your screen right now).

**gold007eye** · 03-22-2006, 11:51 AM

Yeah the P1900 supposedly is a 140W PSU and startup/shutdown controller. If I could use the carnetix psu to power the fans any idea on how I would do that? The fans I ordered have 3&4 pin connecters (molex). The other thought on that was I wasn't sure if the Carnetix would have enough Wattage to handle MiniPC and 4 Fans. Any ideas? I don't have any of this hooked up yet, just doing the prep work. Somehow I guess I can power the MiniPC using the Carnetix.. I'm not exactly sure how I will be doing this though.. so any suggestions would help.

**DCU1976** · 03-22-2006, 12:06 PM

The fans are 12 volts correct?! Why not wire the fans into an ignition output, that way, whenever you turn the key in the "on" position, the fans come on with the rest of the car, or you can either wire them directly to the battery with a switch(fused of course) and control them manually. Just a thought.

**gold007eye** · 03-22-2006, 12:17 PM

That's an idea. I am trying to run as few wires to the battery/ignition as possible though. I am trying to keep it so that the box is pretty self contained under the drivers or passengers seat with minimal amount of wiring. Unless I could some how hook up a distribution block in the "box" that connects to a ground & ignition 12v+ line. If I were to do this where would be the best place to splice into the 12v+ ignition line? Should I use the same line used for the radio? or will that cause a short later on? If I could somehow connect a line from the battery to a distr. block in the "box" that would only receive power when the car is on that would be the best solution. I just figured that a PC PSU would be the quickest/easiest solution?