HD TV motion blur

[yetanotherid]

I have a Winfast PxDTV2300H HD digital PCI card.

The motion blur only happens with HD video (or with SD video it's not very noticeable), but it's there watching either live or recorded TV. If I convert the same recorded video to something progressive the motion blur disappears so I figure it's a de-interlacing issue? Only I've no idea who to blame.

Where I am the normal TV refresh rate is 50Hz. I've got my CRTs refreshing at 85Hz. They don't go as slow as 50Hz but I've tried other refresh rates without any improvement. I don't even know if any of that's relevant to digital TV.
I've tried playing the video back with different players and still experience the same problem. I'm pretty sure at one stage I tried Media Player Classic and FFDSHOW with de-interlacing disabled. Lots of interlacing lines etc (as you'd imagine) but no blur as such.

So is it the TV card's fault, the video card's fault (nvidia 8600GT), more crappy nvidia drivers or is it something else?

Any suggestions would be appreciated.

[yetanotherid]

Well it's got me beat but for the moment the problem seems to have gone.

Last night I restored a 6 month old Ghost image to the PC, updated some of the software, ran Windows update and updated pretty much all of the drivers.
I then installed the Winfast card (I didn't own it when the Ghost image was made).

I then fired up the card and even HD stuff seems to be motion blur free. I guess it's good news, although if I knew what was causing it that'd be even better....

[ACrowley]

Your Problem should be the wrong Combination of GPU Drivers/Settings and Playback Decoder.
Is it H264 or Mpeg2 ?

You should use Hardware Deinterlacing and DXVA. Use EVR Renderer, Cyberlink or Arcsoft Decoder.