I've recently installed Windows 7 and GBPVR on my HTPC (previously WinXP + GBPVR) and was looking at the codec options.
I was hoping to use the built-in MS DTV-DVD codec as I believe it uses hardware acceleration when used with the EVR renderer. When I tried the MS codec and GBPVR's EVR renderer, I got no picture or sound. Using the VMR9 Fullscreen-Exclusive renderer and MS codec works but the CPU utilisation is around 60% - i.e. there's no hardware acceleration going on.
I tried installing PowerDVD 9 Ultra, but after install it's H.264 codec wasn't listed as an option for GBPVR to use. In the end, I went back to the codec from PowerDVD 8 with the EVR renderer, and everything seems to be fine - 10% CPU usage and good quality playback.
Should I be able to use the MS DTV-DVD codec with GBPVR's EVR renderer to get hardware-accelerated H.264 decoding, or does the codec only provide hardware acceleration when using Media Foundation (or whatever it's called) with MCE?