I find my ATI4870 blows away my Nvida 8800
This is not unexpected since it is a newer card and a much faster cpu and memeory, etc. I find it hard to believe the ATI is a no-show for this setup you want to do.
I'm runnig Vista x64 and the ATI4870, I also have Vista x32 and the Nvida 8800, The nvida machine almost always has lag and display drawing is aways delayed. The sound on this machine can sometimes be 5-10 seconds behind the other two machines. I have not been able to figure out where this delay comes ( vista x32 or the nvidia card or the combo of both or maybe sometype of NIC problem, I just don't know ).
each machine is running two copies of wow.