Call of Duty 4: Modern Warfare
Game uses heavily modified Quake engine and it's greatly optimized, even older biulds can run it with a steady framerate.
Version Differences
Game is available in retail and later was released on steam. A valid CD-Key is required to play online.
Patches
There are 7 patches but you only need last two.
These two patches are around 300MB in size.
Tweaks
Game is highly customizable by using console commands. You can enable console in game's options.
Show FPS Counter
- Enable console in options
- Press tilde (~)
- Type in cg_drawFPS 1