Is anyone using PowerNow with their S939 Opterons?

I'm getting mine next week, finally moving away from Intel, and I thought PowerNow on an OC'ed Opteron would be a great thing..

I leave my PC running 24/7, and there's really no need for it to be running full voltage and full clock if it's just downloading some stuff off the web or checking emails.

I've read on DFI's site that you shouldn't use Cool'n'quiet if you're overclocking, which raised my concerns about PowerNow..

Can this be done?

I thought it only dropped the multiplier (voltage too?).
Can the levels be set?

I'll have a mCubed tbalancer in the box, and it would be really cool to drop all the fans to zero or very very low and have the CPU running at a low clock and low voltage until it's needed to do some actual work (like games or video of course!)