I have to many fans, and not enough headers on the motherboard. Powering them isn't a problem, but I want to be able to monitor their speeds.

I have been told that it is possible to have more than one sense / tach lead connected to a header, but it requires special software to decode the cobined pulses of the fans.

Is this possible, and if so, does anyone know of software or techniques that can do this?

Thanks in advance,