Its seems to me that its not so much the 8500 is slow in ut2k3 but the gf4 is exceptionally fast in high detail.
At medium detail the gf3s 8500s and gf4s had little difference in speeds but in high the gf4s shot ahead leaving the gf3/8500 behind.
The amount they are ahead by suggests either specific game optimizations for gf4 only or the gf4 isn't actually rendering completely.
When the final demo build comes out there will be some reliable and verifiable results around so its probably best to wait till then.
At medium detail the gf3s 8500s and gf4s had little difference in speeds but in high the gf4s shot ahead leaving the gf3/8500 behind.
The amount they are ahead by suggests either specific game optimizations for gf4 only or the gf4 isn't actually rendering completely.
When the final demo build comes out there will be some reliable and verifiable results around so its probably best to wait till then.