Nvidia 8800GTS vs ATI X1900XTX - PCI Express 16x

[joepic]

http://www.tomshardware.com/2007/03/27/pci_express_scaling_analysis/index.html

Conclusion

The conclusion of our 2004 PCI Express analysis was simple: x4 PCIe bandwidth typically was sufficient to run single graphics cards without creating an interface bottleneck. At that time, x8 or x16 link widths were not necessary, and AGP was still powerful enough.

However, the situation clearly is different today, as we found that only four PCI Express links are no longer adequate. Although there are differences between ATI/AMD and Nvidia, and between games and professional graphics, most applications deliver best performance at x16 PCI Express speeds. The two 3D games we used - Quake 4 and Call of Duty 2 - certainly cannot be called demanding these days, yet they benefit somewhat from faster link speeds. The professional benchmark SPECviewperf 9.03 was the real eye-opener, as it categorically disqualifies PCI Express link speeds below x16.

The benchmark results make pretty clear that chipsets and motherboards need to be capable of supporting all graphics cards at the full x16 PCI Express speed. If you run high performance graphics cards on inadequate interfaces such as PCI Express x8, you give away performance.

[BJ_M]

the number of high performance graphic apps that require that performance is so small as to be not a factor ....

its not like PRO-E is mainstream ..... and almost no editing applications require it ...