I had no problems with my GeForce 4 MX 4000 with CS:S, as the whole Source-engine is so CPU dependet, that even a poor GFX solutions will be doing fine enough for low settings with DX7. (Not a constant 100FPS, but it stays above 60 for most of time, if the CPU is sufficent.)
...unless you are THE übergamer (Having 1600x1200, 8xAA, 16xAF and EVERYTHING @ ÜBER-HIGH settings is a
MUST, or otherwise it looks UNPLAYABLE). Those poor rednecks shouldn't be using steam. ...

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