Video Processor and Power-Saving Technologies

PureVideo HD video processor within G200 has come here from G84/G92/G94 as is, without any changes. All previously described innovations, such as support of two video streams decoding, compatibility with Vista Aero interface, dynamic contract and color balance adjustment were made on the software level back at launch of Nvidia GeForce 9600 GT.

The main disadvantage of PureVideo HD compared with ATI UVD/UVD2 is still the absence of fully-fledged support of hardware HD video decoding in a popular VC-1 format. In this case, such resource-hungry task as primary video stream processing including entropic algorithms decoding, is performed by the system CPU. Nvidia G200 also doesn’t have a sound core that has long been an inalienable part of all ATI GPUs with unified architecture since R600. This proves the hypothesis that they designed G200 very hastily, trying to make it a leader in the high-performance GPU segment at any rate.

When working on a new high-performance graphics processor, Nvidia couldn’t help paying special attention to power consumption management tools, because a large and complex chip like G200 cannot consume little power by definition. One of the most important goals was to make it more economical in idle mode and in applications that do not utilize the core 100%, such as HD video playback, for instance. Therefore, they provided G200 with the opportunity to adjust not only the frequency, but also the voltage on its functional units and even disable some of these units if they weren’t needed at the moment.

G200 also fully supports HybridPower technology that we have already described in detail in one of our previous articles. It implies that a graphics card may get completely shut down in 2D mode transferring its functions to the integrated graphics core of the system chipset. For HybridPower to work you need a mainboard based on one of the following chipsets: Nvidia: nForce 780a, nForce 750, GeForce 8200 or GeForce 8300.