Noise levels
Noise levels were measured using an Extech Digital Sound Level meter placed 1" from each card's PCI back plate, out of the direct path of air flow. Measurements were taken after 10 minutes idling on the Windows desktop, and again after 10 minutes of running 3DMark06's Return to Proxycon test at 1600x1200 with 4X antialiasing and 16X aniso.

With its low fan speed setting, the Toxic is every bit as quiet as a stock Radeon X1900 XTX at idle. The high fan speed setting is also quieter than a stock XTX under load. However, neither X1900 can match the GeForce 7900 GTX's comparably quiet noise levels.

Note that the Toxic card's noise levels don't change between idle and load. Since its fan speed control is switch-based, it doesn't enjoy the automatic idle fan throttling found on the GeForce 7900 GTX or stock Radeon X1900 XTX.

GPU temperature
GPU temperatures were measured using Everest Ultimate Edition using the same idle and load conditions as our noise level tests.

At idle, the Toxic does a much better job of cooling the X1900 XTX than ATI's stock air cooler. The liquid cooler's advantage extends under load, where it keeps the graphics chip 10-12 degrees cooler, depending on the fan speed used.

Despite being nearly seven decibels louder, the Toxic's high fan speed setting doesn't yield dramatically lower GPU temperatures than the low fan speed setting. That's a disappointing result, but at least you won't have to worry about opening up the case to switch between settings.

Power consumption
We measured system power consumption, sans monitor and speakers, at the wall outlet using a Watts Up power meter. Power consumption was measured at idle and under load using the same conditions as our noise level tests.

Power consumption is largely consistent between the stock and Toxic X1900 XTXs. The GeForce 7900 GTX draws less power at both idle and under load, though.