We measured total system power consumption at the wall socket using an Extech power analyzer model 380803. The monitor was plugged into a separate outlet, so its power draw was not part of our measurement.
The idle measurements were taken at the Windows desktop. The cards were tested under load running Oblivion at 1920x1200 resolution with 16X anisotropic filtering. We loaded up the game and ran it in the same area where we did our performance testing.
The GeForces were all measured on the same motherboard, but we had to use a different board in order to run the Radeon X1950 XTX in CrossFire, so keep that in mind.
The other thing to note here is that, for all its speediness, the Ultra draws substantially less power than the dual-GPU solutions that offer similar performance.
Noise levels and cooling
We measured noise levels on our test systems, sitting on an open test bench, using an Extech model 407727 digital sound level meter. The meter was mounted on a tripod approximately 14" from the test system at a height even with the top of the video card. We used the OSHA-standard weighting and speed for these measurements.
You can think of these noise level measurements much like our system power consumption tests, because the entire systems' noise levels were measured, including the Zalman CNPS9500 LED we used to cool the CPU. Of course, noise levels will vary greatly in the real world along with the acoustic properties of the PC enclosure used, whether the enclosure provides adequate cooling to avoid a card's highest fan speeds, placement of the enclosure in the room, and a whole range of other variables. These results should give a reasonably good picture of comparative fan noise, though.