Noise and Power Consumption
Our earlier tests showed that the reference cooling system Nvidia installs on its new-generation graphics cards is not only efficient, but also quiet. It rivals the leaders of the past in that parameter. We mean the coolers of the GeForce 7900 GTX and Radeon X1950 XTX. Despite the increased frequency of the main domain, the cooler of the XFX GeForce 8800 GTX 768MB DDR3 XXX Edition behaves just like the coolers of the non-overclocked versions of GeForce 8800 GTX, i.e. very quietly even under 3D load.
With 681 million transistors in the graphics core and a shader processor frequency of over 1GHz, G80-based solutions can’t possibly have low power consumption. We performed our power consumption tests on a special testbed equipped with connectors for measuring instruments.
- Intel Pentium 4 560 CPU (3.60GHz, 1MB L2);
- Intel Desktop Board D925XCV mainboard (i925X);
- PC-4300 DDR2 SDRAM (2x512MB);
- Samsung SpinPoint SP1213C HDD (120GB, Serial ATA-150, 8MB buffer);
- Microsoft Windows XP Pro SP2, DirectX 9.0c.
The measurements were performed with a Velleman DVM850BL multimeter (0.5% accuracy).
We loaded the GPU by launching the first SM3.0/HDR graphics test from 3DMark06 and running it in a loop at 1600x1200 resolution and with enabled 4x full-screen antialiasing and 16x anisotropic filtering. The Peak 2D load was created by means of the 2D Transparent Windows test from Futuremark’s PCMark05 benchmarking suite. We did not test the XFX GeForce 8800 GTX XXX Edition separately. Its shader processors, which are the biggest consumer in the GeForce 8800, are clocked at the same frequency as the reference card’s, while the growth of the frequencies of the main domain and memory is not as big as to influence the card’s power draw much.
As we wrote in our earlier review, the reference GeForce 8800 GTX from Nvidia refused to run on our Intel Desktop Board D925XCV for unclear reasons. Early samples of reference GeForce 8800 GTX must have had some BIOS-related problems since the newer samples with other BIOS versions work correctly on the mentioned mainboard.
We found out in our review of the MSI NX8800GTS-T2D640E-HD-OC that the GeForce 8800 GTX needed just a little more power than the AMD Radeon X1950 XTX did and its 12V lines, including the internal one, would each bear a load of 40-43W. The GeForce 8800 GTX is not economical in 2D mode because the card does not lower its clock rates then.
Judging by the results, the GeForce 8800 GTX does not really need a very special power supply. A high-quality 450W unit should suffice unless you want to build a SLI subsystem out of two such graphics cards. If you do, you’ll need a 600W or higher PSU with four 6-pin PCI Express connectors. If your PSU has only two such connectors, you’ll have to use power adapters included with the card and power the second card from Molex connectors of the PSU. Purchasing an extremely expensive 900-1000W PSU is not actually necessary even for a SLI configuration with two GeForce 8800 GTX.