Yeah I'm not saying the performance was terrible - certainly not sub 30fps. But it was slowing down in certain places and I expected it (based on the system requirements) to pump out a consistent 60fps.
It sounds like that's not a reasonable expectation with this game on a PIII, and I have no problem with that, I just wanted to make sure I'm getting the most out of the hardware. After refreshing the drivers, etc I can run the game happily @ 800x600 with 32bit colours and high detail, and I think that's about right.
What I should do is some proper bench marking because good performance is subjective and my modern PC is an i5, so I've been spoilt perhaps and am expecting too much. (is that a faux par around here, mentioning modern hardware?).
Thanks again all for your interest.