VR-Zone has done a review on the NVIDIA GeForce 7800 GTX and they found that the popular benchmark 3DMark2005 is especially CPU limited when the 7800GTX cards are run in SLI. Here's a snip:

"NVIDIA claims that GeForce 7800GTX is a completely new GPU architecture and is the most complex GPU ever built. It contains a whopping 302M transistors manufacture on a more mature 0.11 micron process at TSMC. The die size of 7800GTX is still slightly larger than the 6800U although it is based on 0.11 micron compared to 0.13 for the 6800U since it packs 80M more transistors. It has 24 pixel pipelines and 8 vertex shader units compared to 16 and 6 respectively in GeForce 6800Ultra. The core of GeForce 7800GTX is clocked at a 430Mhz, just some 5Mhz more than its the 6800 Ultra and the memory is at 1.2Ghz, some 100Mhz higher than 6800 Ultra."



Link: VR Zone