Help with DirectX VA Hardware Acceleration

I am trying to get the smoothest 1080i playback with the latest Media Player Classic. I first bought an nVidia 6200 AGP8x then I got an ATI Radeon 9600pro.


The 6200 was almost perfect so I wanted to see what ATI can do in the same price range. I plugged the Radeon 9600pro in, loaded NGO 6.4 drivers, and watching recorded 1080i material (NBC late night talk shows) with nVidia Video Decoder -185, and the decoder will not go into Hardware Decode mode, it shows Software YUY1 or something like that, whereas with nVidia 6200 it showed DirectX VA Mode A (idct). In software mode, my CPU is maxed out (Celeron D 3.33G) and video is choppy. I use Media Player Classic with external filters (nVidia Video, CyberLink Audio).


Now I tried all the video tweaks offered by the ati tray tools, even tried 6.3 NGO. No way of getting into DirectX Video Accel. I removed the NGO drivers, cleaned with Driver Cleaner Pro and CCleaner, loaded catalyst 6.4 and I got DirectX VA Mode C (idct) which was very choppy as if it was not full hardware acceleration? No matter what I tried in the CCC for video or even 3D, nothing will bring DirectX VA Mode A like the nVidia 6200. Even removed Cat 6.4, driver cleaner pro, ccleaner, install latest Omega pack for Radeon and still stuck in Mode C. Used the CD that came with the card (Sapphire) and with the old Cat 5.x it still gives only Mode C.


I even used the ATI Video Decoder package (Cyberlink Audio and Video decoders) that was supposed to be optimized for ATI with obvious lack of hardware acceleration compared to using CyberLink on the 6200. The Cyberlink video decoder does not show which mode it is running in, but the nVidia Video Decoder does, and has the Anamorphic mode I like for my 16:9 display.


Finally gave up, cleaned the drivers and registry one last time, plugged the nVidia 6200 back in. Loaded ForceWare 84.21, nVidia video decoder -185, and am enjoying DirectX VA Mode A again, with a bit of jitter on 1080i but smooth 720p and other material. CPU load went down as well.


This is baffling, since both ATI and nVidia advertise MPEG2 acceleration, but obviously nVidia actually works fine, opposite to what I have concluded before I tried the Radeon.


Can someone explain to me the different DirectX VA Modes? And what settings or hardware are they associated with? Any ideas why Radeon 9600pro fails to go Mode A? Thanks.


PS. Fast write is ON, all PCI latency matched to 64, DirectX 9.0c, Video Overlay or Mixer 7 (XP Default), no programs run on startup, pure of any spyware virus, etc.