Windows 7: EVGA GTX 560ti SC and FurMark

I've come across something odd while benchmarking my 560ti prior to trying a bit of overclocking.

While using FurMark 1.9.2 for testing, with EVGA's Precision X open for monitoring, the GPU clock bounces between 450 and 900 MHz (with 900 MHz being the default clock on this card). This is very evident on the "furry doughnut" as it moves faster and slower in a rhythmic fashion.

I noted the FurMark score, closed Precision X and tried again. Got approximately the same score, so I shut down the machine and rebooted. Ran FurMark again without ever starting Precision X but still got the same results.

This GPU clock "oscillation" doesn't occur when I run other tools such as OCCT or Unigine.

Is this normal? Is something amiss or do I have something set wrong?

If you use cpu-z, looking@the gpu frequencies, you have 3 points, desktop, 2d, and 3d. Sounds like you're fluctuating between 2d and 3d. Does the same problem present with afterburner?

^James' point is very valid. To elaborate, 400MHz is the default 'goto' speed for most video cards when running in 2D (desktop) mode. They slow down to this speed purely to save energy, which is an option that can be disabled if desired. In ATI cards this can be achieved in Catalyst, but being unfamiliar with nVidia cards for some years now, I couldn't tell you if the same holds true for the nVidia stock software.

RivaTuner is another option but again, I'm not certain if this program allows such a tweak to be applied. Really, all this unfamiliarity and conjecture doesn't make my post very helpful I suppose.