ATI Radeon X1800 Preview
 

The test results were pretty interesting. Unfortunately I wasn’t able to
run Half-Life 2 on the X1800 XT, since Valve decided to update the code
and break all of the demos that everyone uses for benchmarking. However
Far Cry threw up some interesting numbers. As expected the X1800 XT was
CPU locked at the lower resolutions, much like the 7800 GTX. However, the
7800 GTX was CPU locked at about 20fps above the X1800 XT. The 7800 GTX
remained in the lead up to the point where the CPU ceased to be the
limiting factor - then the X1800 XT edged ahead. I quizzed ATI about this
and was told that the X1800 XT does have a more significant CPU overhead
than the 7800 GTX, but it scales better once the CPU is out of the
equation.

http://www.trustedreviews.com/article.aspx?art=1972