Antec 120mm case fan (Smartcool - thermally controlled). Not spinning fast enough. Need manual override

Hi

I need to vent some more of that nasty hot air out of the PC.

My Antec120mm is quiet but only spins at about 1350 RPM max and and I need
it to spin up around it's max of somewhere around 1900+.

It has a thermal sensor. Can I replace/extend that without too much bother?
OR
I have a manual fan controller in my CoolerMaster Cooldrive 4 that I could
regulate the RPM's with.
Two possible problems with that scenario though:

1. I read the Antec 120mm instructions some time ago and it strongly advised
against mobo fan control such as q-fan.
2. The Cooldrive if I recall, can handle up to 18w of fans connected. It
comes with a 40mm which should only be up to a couple of watts. Antec don't
seem to tell us an accurate wattage for the fan. Should only be a max of 8
watts perhaps? I don't want to blow the Cooldrive up as I only just bought
it.

Fingers crossed...

Thanks

Darren