Great, Thanks.
The X1600 in the iMacs is very sluggish... even more so in the MacBook Pros.
I assumed that being a Mac Pro, the graphics card performance would be better. The only other alternative to the 7300 GT in the Mac Pros is the X1900XT which is a very unstable card, screen tears, overheating.... etc.
Hopefully the next Gen. Mac Pro's will have a better card.