How do I make hd4870 control a 3 or 4-pin fan?

[oldswab]

Hi folks,

I put a thermalright HR-03GT on my 4870 along with their VRM-R2 (I should have gotten the -R1 since I have a top down cooler, but that's another headache) and was wondering if someone had a diagram or some clear instructions on how to convert a 3-pin (case fan) or 4-pin (arctic cooling cpu fan I have laying around) to be controlled by the card instead of plugging the fan into the mobo. I would rather not cannabalize the old wires off the stock cooler in case I want to sell it later, but would be willing to as a last resort.

 

[Gzero]

You have usually 3 wires. Black(earth), yellow(12v), and red (5v). You may need a soldering iron to connect the wires to pins.
You would have to convert the fan to work only on one feed(not sure how much the card connector puts out).
:>

Don't ask me which order you need for the 3 pin motherboard connector since I usually use trial and error wrecking the rpm sensing on the mobo lol.

 

[mastrdrver]

You can cut off the connector from the fan that is on the cooler and wire it in place of the connector on the case fan. You won't be able to control the speed of it though.

The three wires on the case fan are: red (12v), black (ground), and yellow (rpm speed). There is no 5v present on a case fan connector.

 

[oldswab]

Thanks for the replies. I just went ahead and plugged it into the mobo--it's a big, slow fan so even at 12v the acoustics aren't terribad. I did check the temps at various times while in heavily rendered areas of my favorite games, LOTRO and BF:BC2. It stayed between 60 and 63C under load, so overall I'm pleased.