Sakumo

Borderlands: Can't say for sure since I don't have the game, but from what the recommended says, you should be able to run it smoothly.
COD4: it depends on the server, but it doesn't require an extremely high end PC to run it at max, my brother had a 8600GT(equivalent to a 9500GT) was able to run it on mostly high and a few medium and received about 50-60FPS on multiplayer with 32 players.
COD:MW2- I'd say about the same as COD4 since it uses the same engine(well should, since it's suppose to be the same as WaW,which uses the COD4 engine).

Also, join the people upset with IW, and boycott the game until they give the PC users what we deserve, which is user custom content and dedicated servers, for being forced to update our PC every time they use a new engine.

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