Elite Bastards posted a review on the NesteQ FanMax 8-channel fan controller

As you might have guessed by now, the FanMax takes up a single 5.25" drive bay in your system, with the front panel exposed at the front of the chassis as you see above. This panel gives you control over each of the eight fans that this unit supports via a speed control dial which effectively controls the voltage fed to that fan between 6 and 12 volts to adjust its speed, while these eight fans can also be split into two "group" of four fans.

NesteQ FanMax 8-channel fan controller Review