relatively high output 120mm fan with 3 pin connector???

[Spyda]

can you get a 120mm fan with a 3 pin connector from anywhere? i want to remove the shroud on my Tt volcano 7+ and get a powerful 120mm fan and a zalman fan bracket for more CFM cooling power, but the only 120mm fans i can find are all 4 pin

Cheers

[scott_d]

I dont know if they ship to the UK, but it is worth a look...
http://svc.com/12bluquadled.html
They have other 3-pin fans, but this is just the first I came across in the list.

btw...why do you want a 3 pin connector? just curious..

[Spyda]

cos i have a resistor switch that connects to the PSU by a 4pin and then connects to a fan by a 3pin

[Spyda]

they would be ideal but alas, no UK shipping and the airflow isnt very high :(

i was looking at about 80+ CFM

[mattg2k4]

Do you really need the RPM monitoring?
Some systems don't boot up without a cpu fan RPM reading, if that's what you're worried about just plug a 3 pin case fan into the header, assuming you have one.

[Spyda]

i want to be able to control the rpms for noise, when playing games etc, whack it up to high rpms, when on the internet etc, put it on low/quiet

[mattg2k4]

You don't need a 3pin connector for that. There are many ways to accomplish that which works perfectly well with a 4 pin connector. You could buy a professionally made rheobus, do a 7volt mod, buy a potentiometer and wire it yourself, or even build a pulse width modulation circuit based on the 555 chip (easiest way to accomplish PWM), or a voltage regulation circuit based on the lm317.

The 7 volt mod, hooking the 5v line to the ground of the fan in case you didn't know, is a very easy, fast way to slow down a fan. Get a on-off-on switch to switch between the fan being on @12v, @7v, and off.

The easiest way to get a wide range of speeds would be to purchase a potentiometer. I don't know offhand what value would be best, but you can use ohms law, voltage=current*resistance to try to calculate a good value. You know the current draw of the fan, it's usually printed on it (although it will change, I think downward, as the fan slows down), then say you want it to go down to 7 volts, you have only the resistance left unknown in the equation. Also calculate the power dissipated by the potentiometer (voltage dropped*current draw of fan) and by a pot with a higher wattage rating than this.

[scott_d]

He already has a rheobus.
I've seen 3-4 pin adapters that would work. Look for one of those

[Spyda]

any idea where you can get 4pin to 3pin in UK? ive only seen 3pin to 4pin

[mattg2k4]

If you have any computer fairs in the area, I'd check there for a 4-3 pin connector.

If you can't find one, it wouldn't be hard to make one yourself. The yellow wire on a 4pin connector is 12v, and the black wire is 0v. I'm not sure if there's a color standard for 3 pin connectors, but on mine, black is 0v and orange is 12v. If you have the female 3 pin connectors facing you with the connector holes at the top, the order from right to left is 12v, 0v, rpm. Just get a 3pin from an old fan and do a quick solder and heatshrink job.

You could do also switch the 3 pin connector on your resistor for a 4 pin, using an adapter or another solder job.