PureVideo and the AGP GeForce 6800
When the 6800 first came out, NVIDIA advertised it with their new on-chip video processor dubbed PureVideo. Purevideo was claimed to decode, encode, and play several video formats while taking much of the load off the CPU. It also included some other features like advanced de-interlacing. But it's most attractive feature was hardware-assisted decoding of WMV HD, a relatively new codec.
In WMV9 playback, user and web reports have shown little if any difference between Purevideo enabled Geforces and non-Purevideo cards. To add to the confusion, NVidia has been unclear about the status of WMV9-playback and PureVideo. NVidia has admitted (in private communications to vendors) that the NV40/NV45's PureVideo unit may be missing the WMV9 component. But in public, NVIDIA has merely acknowledged the absence of WMV9 support in its driver-set, promising the functionality would be added to a future release.
On all other members of the Geforce 6 family (the 6200, 6600, PCIe 6800/6800LE), WMV9 testing has demonstrated a marked improvement in CPU-utilization over the baseline AGP 6800. The prolonged silence of NVidia, after their public promise of updated drivers, and test evidence gathered by users has led the user community to conclude that the WMV9 component of the AGP 6800's Purevideo unit is either non-functional or intentionally disabled. All other aspects of PureVideo (MPEG-2 decoding, deinterlacing, HQ-scaling) appear to function within specification, on all Geforce 6 products.