To calculate the power consumption of the video cards, we measured the power draw of the entire system. We used the same exact hardware for each test platform. The components are listed below:

• motherboard: Abit AW9D-Max ( Intel 975X chipset)
• memory: Corsair CM2X1024 6400 (3-4-3-9) @ 800 MHz; 2x1 Gbyte
• hard disk: Western Digital WD1600JS - Serial ATA - 7.200 rpm, 160 Gbytes
• processor: Intel Core 2 Extreme X6800
• power supply unit: Tagan TurboJet TG1100-U95 (1,100 Watt)

We tested the power consumption at two power states; idle and full load. Idle consisted of a blank desktop loaded in Windows XP Service Pack 2.0 with the bare minimums of processes running. Full Load tests were calculated with ScienceMark 2.1 running at a resolution of 2560x1600.

In both instances, we see the 320 MB GeForce 8800 GTS drawing in more power than the 640 MB GTS reference board. It is important to remember, however, that the 320 MB sample we were testing with had been clocked beyond the default frequencies. The reference 640 MB 8800 GTS, on the other hand, had not been overclocked.

To gain more of an idea of the true power consumption of the 320 MB 8800 GTS, we also included the power consumption of XFX’s overclocked 640 8800 GTS in our tests. The overclocked 640 MB XFX GTS card was running at the same GPU frequency as our 320 MB sample, while its memory was clocked 40 MHz higher. As can be seen, in both cases the overclocked 640 MB GeForce 8800 GTS consumed more power, and ended up consuming nearly 20 more Watts under full load.