HDTV cause decreased performance?

I have a pretty nice system 2600k 4.8ghz and a GTX680.  I get really high frames but for some reason, FSX just does't seem smooth.  I have used the "tweaking tool' that everyone uses on they're CFGs and get very good frames but my eye sees some stutters. I was thinking maybe my memory but I feel like I have good memory at DDR3 1600Mhz using 9-9-9-24. I feel if I was using a computer monitor instead of an HDTV maybe the intangible "smoothness" would be better. The only time I see true smothness is when I'm at Midway Island and I get 200-ish FPS. Yeah, I know that's a lot of FPS!