Power and Temperature 

We measured the temperatures on idle and under full load. The power consumption is measured for the entire system. In all tests we used identical components, apart from the graphics cards, of course.

In idle mode, all cards are pretty cool. We used an Arctic Cooling 12PWM fan to help cool the passive cards. The maximum temperature on the 8600 GT was 74°C. We can see that the passive cooling does well on all cards. The 8500 GT AMP, in spite of its active cooler, even on higher clocks, is only 2°C warmer than the 8500 GT Zone at default clocks.

Not surprisingly, the power consumption is highest with the 8600 GT. However, we were surprised that the 8500 GT Zone beat the 8400GS in the full load power efficiency test.