Enemy Tertorial Help.

I have come back home fired up ET but I have a problem. When I play at my normal FPS on a server (76) my screen goes blurry and I can't see it is worse on some maps and better on others. So I have to cap my FPS at 40 which seems to stop the problem. But I don't really want to play at 40 fps. This is what it looks like at 40 fps:

http://img513.imageshack.us/img513/8339/shot0000dk5.jpg


As you can see it is fine no problem, its just the matter of 40 FPS. Now if I try 85 fps you can see the big difference:

http://img513.imageshack.us/img513/5135/shot0001hy4.jpg

I have tried getting the dust of my card (NVIDIA GeForce4 Ti 4800 SE). But that has not worked. I have updated my drivers. But the funny thing is when I play on 2.60B servers I do not have this problem, it only happens on 2.55 any advice would be greatly appreciated. (I know hardly anyone may still pub on 2.55 but if you have any tips or you have had this problem i would greatly appreciate any help).