HTPC issue with GeForce 9600 GT

I have a Nvidia GeForce 9600 GT video card for my personal computer, which until recently has become an HTPC as well. I installed WIN7 Ultimate x64 and running an .mkv (H.264) 1080i video of Transformers and VLC, wmp, powerdvd, etc are incapable of performing the task successfully. I'm using a monoprice DVI to HDMI cable to my Samsung 46" LED TV. I'm using my TV as a second monitor to do whatever and the resolution is 1920 x 1080. When I play DVD's though, there's lines that appear throughout the picture when the camera is panning. Why i'm facing HTPC issue with GeForce 9600 GT? Can anyone confirm that the video card is the culprit? If so, what Video card do you recommend? Kindly help me out to resolve the above issue. Thanks.

You need to use a video player that supports hardware acceleration. Are the videos you are trying to watch bluray HD files or just plain video files. Because just plain video gets worse looking the larger the resolution as you stretch it out of its intended resolution.

I am playing regular DVD's. I should have added that I lowered the resolution significantly and the problem still persists. I can play a 1080p movie without hardware acceleration (Windows Media Player) on my ION rig, it's ugly and stutters, but it works. Same file works great in Media Player Classic. I understand what you are saying though. What kind of GPU do you recommend that can do what I need it to do?

I don't think the video card accelerates anything other than mpeg-2, and then only with specific players. This is most likely a codec issue if the OS isn't burdened down with crap. Are you using the same versions and codec on both machines? By the way, there are several versions of the chips you named.

Get the latest drivers for your motherboard, sound card, MS windows(whatever) Update the video playing software. Are you using the latest drivers from the nvidia website? Take the computer off the network and turn off all the virus checkers and fire walls.

It only works with certain video cards, although I wouldn't think there would be much difference in this between a 3450 and a 3650. The video card will be the only item housing a smaller fan but this should not cause undue noise while using the system for desktop or media usage since the GPU won't be taxed so there will be minimal heat generation.