Is this to do with fill-rate?
Yup - okay that's some homegrown FX out of the window right there.
I had a b3d project(kinda poly heavy 170k but low surface count ,around 150) that would run at 90-105 fps on a 5900fx (1800+ athlon)
that ran around 12fps on the mirage
Thanks for the info - those figures aren't too discouraging I guess [thinks back to Saturn Quake's framerate].