Hardware Acceleration + VMR9 stutter

[Scudo]

I just want to say that I realize this is probably not GB-PVR's fault, but you guys seem to be very knowledgeable and I'm not exactly sure where to turn...I've contacted Nvidia about this issue but they still haven't responded. If anyone can point me towards a forum more appropriate, I would appreciate it.

Basically, my problem is that enabling VMR along with hardware acceleration causes frequent stuttering. In GB-PVR, I have tried VMR7, VMR9, and VMR9 Custom and the results are the same. I have used both the Nvidia Purevideo Decoder and the Cyberlink Video Decoder and, as long as hardware acceleration is enabled, it's jerky. Once hardware acceleration is off, the problem vanishes. Overlay mode seems fine too.

I would really like to be able to use hardware acceleration with VMR, because the picture looked noticeably better than Overlay or VMR without acceleration (I guess it takes advantage of the Geforce 6 and 7 series hardware deinterlacing?). CPU usage was also greatly reduced (usually hovering at about 10-15%, as opposed to 30-50% without acceleration). I'm just watching standard analogue cable, I would think my graphics card could handle it.

Does anyone else have this problem, and if not, where I should look for help? Searching google yielded me plenty of mentions of hardware acceleration causing problems with VMR9, it's what gave me the idea to turn it off, but I can't seem to find a solution.

Some system info:
Windows XP (with SP2)
Geforce 7800GT (latest 93.71 drivers, though it was present on the last set as well)
Athlon64 3500+
ATI Theater 550 Pro (latest drivers)
2 gigs of ram
Purevideo decoder (latest, though it's seemingly any decoder that can use hardware acceleration)

[diehard2]

There's a thread around here about replacing quartz.dll for directx. Its kind of an annoying kludge, but its effective. The only danger is that sub will decide to use some features of the VMR that are only in the latest version of the quartz.dll. I find that fast forwarding fixes the stutter for me, even if I'm at the beginning of the buffer. Perhaps is a small fast forward were added at the end of every command it would fix things... Who knows?

[Scudo]

I did try the DirectX 9.0b quartz.dll earlier, but it didn't make any noticeable difference. This occurs while watching in Live Preview mode, so I can't fastforward...I tried that out on a recording, but again, I'm afraid it didn't help. It's weird, I can use hardware acceleration with Overlay Manager and get smooth playback, and I can use any of the VMRs without HA and get smooth playback. I might try the older quartz.dll again tonight, just for kicks. The last time I tried it was before I realized that enabling HA was caused the stutter.

[allsighs]

I had a problem on when I upgraded my HTPC from an old ATI output setup to a new Nvidia setup. Stuttering just like to describe. Moving to the old 9.0b quartz.dll coupled with a move to the 89.21 drivers fixed it. any driver after that for me was horrific.

[diehard2]

Well, that's certainly odd. You have more than enough horsepower to run gbpvr. I'm running it on a 1.3 GHz pentium and an NVIDIA 6600 card. I would pull up the task manager, and see if anything else is chewing up the CPU or disk while gbpvr is running (antivirus, etc).