Weird Performance Issues..

[Gothax?]

So here is my problem: I have my computer specs in the bottom, so you won't have to ask for them. When I play ANY game, but lets just put CS:S on the spot light here, I get really strange FPS issue. I have everything on my system updated with all the newest drivers and such, so that cannot be the issue.

Anyway, whenever I play CS:S, I can put all settings at Medium, Shadows at high, AA off, and Reflections to "World", on a resolution @ 1024*768 and get same FPS if I switch the resolution to 800*600 and change EVERYTHING to low.. This is really pissing me off because I'd like to lose some quality for more FPS, although I shouldn't be complaining because I still get 60-100 FPS in action, even though I would like more FPS for reassurance.

Has anyone else encountered this strange problem? Have you come across it and fixed it? Or do you have some tips/advice for me?

*Note - I have AA completely turned off with the nVidia Controller, aswell as Vertical Sync. AND I do not expect to get the BEST performance with this computer, just a bit better than what I am getting.

Thanks alot, guys.

( Make sure posts are on topic, I don't want to have to scroll through loads of crap, thanks )

 

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I am guessing that the problem is tied to the monitor refresh rate. I'm not overly familiar with Nvidea drivers, but perhaps it locks the frame rate to your refresh speed to save its power for other things?