[SOLVED] MOD: 4pin PWM FAN to 2pin header GPU

[diegomayolo]

I need to know "HOW TO" keep fan speed control when connecting a CASE FAN with 4pin cable to a 2 pin header of an expendable Radeon 6770.

I've managed to install the fan, and power it up, but it's running with fixed speed granted by the 2 GPU headers. I think I have clear that 1 of them is "GROWND".

It's the upgrade I was looking for. I'm not having a small and cheap turbine in my silent case, temperatures on the GPU processor stay below 67º in full load (It might get a bit hotter if tested for a longer period, idk).
The PCB and other circuitry feels a lot fresher than it was with the original mini-fan.

So my questions are:
¿ How or what adaptors or wiring could I use to allow the 6770 control the fan according to temps, as normal?
¿Do I need to wire up the FAN's 12v and PWM together an then connect it to the other GPU pin (the one next to Grownd)?

The GPU is temporal, don't care much for it. I have 2 Artic F12 fans (they come with 4pin PWM and 3pin cables).
I'm sorry for my english, thanks in advance for any advice! I know this GPU runs safe with 75º, but i'm not confortable with it, and I can always learn new stuff

 

[anotherdrew]

The 2 pin headers only have a positive and negative (power and ground). Fan speed adjustment (if there is any ... I have seen many that only have 1 speed) is done by adjusting the voltage (12V = 100%, 8V = 60%, etc), though it could be done by current manipulation too. You would have to put a voltmeter on it to find out. It's a very simple fan control. There is no fan speed sensing (3rd pin ... often a yellow wire) and no PWM.

Here is the issue I had with some cards like these. If you use an aftermarket fan, they only run at one speed. I can only guess why (something to do with current draw ??).

In this case, there is no adapter or wiring that will let the fan run "as normal". There are some external fan controllers that will let you manually control the fan speed. For example (just an example, not an indorsement).