Koroush Ghazi, the author and owner of the web site Tweakguides.com has written an excellent article on how to reduce lag in games. As well as explaining the various forms he also gives you the various options to reduce them:
You might be playing Black Ops, Bad Company 2 or Team Fortress 2 online; or maybe you're ploughing your way through enemies in Crysis 2, Fallout: New Vegas or GTA IV. It doesn't matter what the game is, or whether you're playing multiplayer or singleplayer - at some point the dreaded word Lag will be used. That one word sums up a world of frustration for PC gamers everywhere. But what exactly causes this periodic lack of responsiveness in a game? Is there any way to get rid of it, or at least reduce it? Let's get to the bottom of this annoying phenomenon
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