A couple of comments I would like to make:
I've read many times on this board people happy to have 300+ fps with the latest and overpriced vid card.... Beside the technical performance, it won't add a single bit to the eye comfort.
As many have said, leaving VSync on is capital for a smooth video display. If your vid card runs faster than the refresh rate of your monitor, it may lead to partial screen writes and annoying visual effects.
Furthermore, above ~30 fps, it is better to have a stable fps rate than a higher but variable one. I experienced it the other day in Halo: I was playing the game with VSync on (thus locked on my monitor's refresh rate, 75 Hz) but I was noticing some tiny slow downs in intense gunfights (I guess that the FPS dropped in the 50's range). Nothing to make the game unplayable, far from it, but my eyes were catching the fps variations anyway... So I decided to experience with the 30 fps rate setting of the game. Well, the game runs surprisingly smoother! Even if the fps are now constantly less than they were during a slow down, the stable output is much more comfortable to the eye.
I decided to try it in AHII (where I got 75 fps almost everywhere but it could drop to 55 fps with intense smoking) and locked it at 45 fps. Again, it was much more pleasing to the eye and, honestly, I can't tell the difference between a stable 75 fps and a stable 45 fps.
About LCD monitors:
I've read here and there that LCD monitors were not as good as CRTs for gaming. I think that the recent LCD models are now as good as CRTs while not as tiresome to the eye. However, you'll have to choose carefully.
Most constructors give now the response time as characteristic along with resolution and contrast. In theory, the lower response time is better for gaming. However, the figures can be highly misleading, because the way to measure the response time is not realistic.
In a nutshell (and if I recall it correctly), the response time is the delay for a pixel to switch from black to white. One may think that this is the worse case scenario...far from it! To switch from black to white, the pixel controller only has to apply full voltage. But to switch from one gray shade to another, the controller has to apply voltage and adjust it according to the result (the classic control loop in automation systems). So if the quality of the pixel component plays a major role in the measure, the quality of the controller plays an even greater role in the day-to-day use.
Furthermore, the technology used plays another important role. There are 3 major technologies used in LCD screens: IPS (In Plane Switching), VA (Vertical Angle) and TN (Twisted Network). Honestly, I don't know how they work and what it actually means. I only know that, while IPS usually have very good response time figures (12-15 ms), they are poor for gaming. If I'm right, VA are limited to 25ms but are much better in this aspect. I think that TN screens are half-way between both.
I've noticed that most constructors don't mention the technology used. One way to distinguish between them is to check the angle of vision: IPS screens usually have a broader angle than VAs.
All this info comes from a french article that I haven't bookmarked but I'll try to find it back. In the meantime, it would be interesting if somebody could point to an english source on the same topic or correct the mistakes I've probably made in my explanation.
