So I've been having some issues with my video playback, but I'm not sure what the the cause, so I'm not sure if it's my GPU. Basically, I just upgraded my TV to a 1080p Insignia, which I have hooked up to my PC as a second screen, so that I can watch movies on it. I opted to get one with a 120hz smoothing feature (mainly for sports, which looks good on it), but I found that watching videos from my compy resulted in missing frames on a fairly constant rate (depending on the video). I did a bit a research and found that the 120hz options commonly causes this problem and couldn't find a good way to fix it. I turned off 'cinema mode', with some success, but decided to turn off the smoothing to see if that would help. It seems to help with some of the video rips I have, but some of them (typical bigger files in 1080p) still show some slow down, and it seems to be worse on my TV than on my monitor. That being said, I know that a bottleneck for my system is my pretty outdated GPU. It's an ATI Radeon HD 4800. My processor is an AMD Phenom II x4 965 Processor 3.4ghz with 8192 mb of RAM. I know that GPUs can definitely slow down video playback of bigger files, but it seems weird that it's worse on the TV without the 120HZ smoothing on. My question is, what can be the cause of this problem? The TV or the connection to it (HDMI), the GPU or some other system problem, or the rips themselves? Is you can't tell, I'm not the most tech-savvy, so any replies that aren't 50% acronyms would be greatly appreciated.