Odd graphics glitch! Please help!

This is difficult to explain but I will try.

First, I guess you will need to know my system specs so... I have a new Core 2 E6600, P5W DH, 2GB PC5400 and a Sapphire X1900 GT. I do not overclock, it is all stock. The GPU driver is Catalyst 6.6.

Anyway, while playing games I occasionally see a horizontal 'slice' all the way across the screen. Its not that bad or common but is noticeable. As I say, it is hard to explain but it looks like part of the image sticks for a split second before updating the image. Its almost always in the same spot too. Another way to describe it would be as a 'flicker' but only in that line.

I'm thinking it could be my monitor, but could be the card. The monitor is an old, but otherwise OK, LG 17" F700B CRT. It could be the screen resolution which is currently 1152x864 in XP and games.

Does anyone even know what I am talking about and if so, can you help?

Thanks. I'll try that. To be honest I have played one or 2 otehr games recently and kept the resoltuion down a touch. It seems fine like that so I now think it was just a monitor thing.

I appreciate the help.

Thanks. I'll check the Vsync setting later.

As for my monitor, its an LG 17" CRT.