Speedfan reports that it idles at 80% (~9.6V) and ramps up to 100% (12V) at 100% CPU load.
I'd bet the voltages are more or less different than the calculated values. Most, if not all motherboards use PWM to control the speed, and depending on the design, with low-current fans, the "voltage" range is not what one would calculate on paper.
You could test the fan with Zalman Fan Mate (or similar fancontroller), and measure the voltages/temperatures. Your load temps seem OK if your room temp is more than 22Â°C, and/or the temp doesn't climb much higher than the present.