Are these full load temps?
Idle temps mean absolutely nothing.
Fire up a CPU intensive program like RC5, Seti@Home, Prime95 and then record temps after 30 minutes. I doubt a VolcanoII would be posting temps like the ones above. The C/W rating would be it in the region of Alphas, GlobalWins, Tiasols etc. with high CFM fans. For example, I calculate Dan's C/W rating of < 0.22(using 1.5Ghz and 1.85V, on the conservative side). That's almost impossible for ANY cooler to achieve with the ~23-25CFM fan it uses. Just can't happen.
IMO, this cooler will work for AMD systems below 1Ghz. You will have high temps, but it'll get you by. For a high OC rig, spend some more $$$ and get something decent.