Starting with the GeForce 6 series, NVIDIA begun to bolster the video processing capabilities of its graphics cards with the addition of a dedicated processor along with software and driver support, collectively named PureVideo technology. This move was in line with the growing use of high-definition video codecs like H.264, VC-1 in movies and HD media content. PureVideo helps to accelerate this as well as other common MPEG 2 and WMV media content by relieving some of the processing off the CPU and on to the GPU. Additionally, PureVideo also had processing to ensure quality of the video stayed true as it was intended. In more recent times with the various developments in HD media formats such as Blu-ray and HD DVD, NVIDIA has subsequently added to this technology for the GeForce 7 series, with a new version known as PureVideo HD that brings proper hardware acceleration to the table for HD media playback.
While it is true that having a PureVideo HD capable GeForce 7 graphics card reduced CPU utilization when playing back HD movies on a PC, it is not perfect and NVIDIA itself acknowledges that by stating that a dual core processor was still recommended for optimal HD video playback. The next step is obvious and that is something NVIDIA has now claimed to achieve with the new GeForce 8600 and 8500. These cards feature a newer and presumably improved video processor along with an integrated bitstream processor to enable full HD decoding. According to NVIDIA, these mainstream GeForce 8600 and 8500 cards are the world's first video processors to almost completely offload the processing needed for both HD DVD and Blu-ray video playback. Although we're always wary of superlative claims like these, we believe that at the least, the new cards will massively reduce the HD video decoding workload from the CPU. As seen in the CPU utilization chart below presented by NVIDIA, we concur with their findings for a system with and without PureVideo HD as we've found out first hand in this article . All that's left now is to verify if processing overload on the new GeForce 8600/8500 class stays true to the chart and we'll look into that area as soon as we've acquired the right components again.
The new video processing engine will only be found on the GeForce 8600 and 8500 at the moment and are actually embedded within the G84 and G86 cores respectively (and soon the upcoming GeForce 8400 series using the G86 core will also support the new video processing engine). Hence, the older but faster GeForce 8800 series will not have this hardware, giving rise to the possibility that there will be lower CPU utilization numbers on a system equipped with a GeForce 8600/8500 as compared to a more expensive system featuring a GeForce 8800 GTX. NVIDIA has said that they believe users who have chosen the more powerful (in 3D performance) GeForce 8800 GTX are enthusiasts who are likely to possess very capable systems. For these users, gaming performance is paramount and the GeForce 8800 is still extremely competent for HD video playback, especially coupled with the high-end CPUs found in these systems. Therefore, for the near future, we are unlikely to find the new VP2 and bitstream processor on the GeForce 8800 (not even in their upcoming GeForce 8800 SKU).
Furthermore, NVIDIA has assured us of PureVideo HD support in Windows Vista for both the GeForce 7 and 8 series. However for those using Windows XP, the new GeForce 8600 and 8500 cards will only have PureVideo HD support in June 2007 so you may want to wait a bit if you're on the older operating system.