fan control app
 

can anyone recommend a good fan speed control app?

Accurately know what are the manufacturer and model of your computer would probably help to give you a relevant answer.

cant lm_sensors control fan speeds? *wondering*

Yes, it uses fancontrol
http://www.lm-sensors.org/wiki/man/fancontrol

I don't know whether a nice GUI app exists. Would be nice. :)

The grunt way to control fan speeds:

* Ensure lm-sensors is installed (true on a stock Slackware).

* As root run pwmconfig, which creates an /etc/fancontrol config file.

* Create an rc.fancontrol script or add something to rc.local to run /usr/sbin/fancontrol &.

* Add monitoring options to a conkyrc configuration or every 15 seconds run 'sensors' from a terminal.