PS, Amps, volts, etc.- can anyone explain this stuff to me?

[Vinny]

Ok, I made a thread about using a PS to power a bunch of fans to cool my entertainment cabinet. A user recommended I get a PS2 console power supply and just rig that to power some fans.

Well, I came upon and bought this.
http://www.coolerguys.com/840556029977.html

And this to connect multiple fans to it.
http://www.coolerguys.com/840556016359.html

Current, in the test phase, I'm using that to power two 92mm Vantec fans.
http://www.newegg.com/Product/Product.asp?Item=N82E16811999603

Now, when I connect the fans to the black 3 pin post, the fans spin fast (like full speed). But when I connect to the white posts, the funs spin noticeably slower.

Why is that?

Also, how can I tell many fans this thing can support? I've been thinking about adding a fan controller too, to control the fans. But I'm guessing that might be overkill?

EDIT* I should mentioned that I did add a Ultra fan controller (directly to the PS, the fans connected directly to the fan controller) and it worked fairly well. I just don't know how to tell how many fans it can support without blowing up or something.

 

[doolittle]

It looks like the standard molex type connector for hdd/cd/dvd/fans and other accessories

Output: 12V +- 2A, 5V+- 2A

The yellow is the +12 and the red is the +5 above, so the red would be your white wire.

Those vantecs are +12/.07A and you have 2 so that is ~0.14A loaded so far I think you can connect a lot more, like 26 more if you need to on the +12.

If you connect them to the +5 then you can have a lot more if needed since the power would drop per fan. I would just use the +5 it's less noise and would probably cool just as well. Don't bother w/ the controller if that is the case 8)

 

[Vinny]

Holy crap... I actually understood that! 8O

And here I was expecting a 10 page article! Thanks!

This make things easier.

 

[rexter]

You can add a controller to the black connector (12V). The controller is basically a resistor that control the current, current drop so to the voltage therefore fan speed drop it correspond to the amount of resistance you're adding in.

Your CS Power Supply can handle 2000 mAmps so you calculate how much current that you connect to this Transformer and do not go over the specified current.

Your fan said 70 mAmps so to let just say 100 mAmps in a safe side, taking into the account that your fan will take more energy when fan gets clog with dust and hairball etc. So this means you can add up to 20+ fans at the same specs of 70 mAmps at 12VDC.

I recommend that you buy a VOM (Volt Ohm Meter) for $15 0r less to be more precise on your calculation.

Just a little bit of information though: Do not stick a VOM to an outlet if is not certified for that uses, you might injure or kill your self. 12V or 24V you’re safe. but with enough current will burn you skin. Use it properly and safely.

edited: VOM also called Multimeter.