I play on 5 year old computer w/
2.8GHZ
1Gig Ram
6800 Nvidia AGP slot but it does have 512mb ram on it

Best thing for me is to turn off all setting in the Video card portion of your computer.

Right Click Wallpaper -> Setting -> Advanced tab in monitor page.

Turn off all Antialising / Anisotropic filtering for all applications, most settings are application based. Besides that I still get mad lag from servers.

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