Most Source games run pretty well on older systems. Before my new laptop, it ran on an even older laptop very well. Now you got a good benchmarktahrey said:Speaking as someone whose computer may or may not be powerful enough to actually RUN TF2, I entirely welcome this news, as I can now try it out (and with it, finally discover if my machine can cope with - yes, try not to faint with disbelief - Portal. As in, "one".) without risking carefully guarded and presumably non-refundable beer money.
If it works, and I like it, I'll happily buy something from the Mann store... and probably the remainder of Orange Box too, if that's still a pay-for item.