iii..i extract some notes from The Nvidia Website.. http://www.nvidia.com/page/pci_express.html
PCI Express
NVIDIA is working hand-in-hand with Intel's workstation, desktop, and mobile engineering teams to help define, develop, and deploy PCI Express solutions.
http://www.nvidia.com/docs/CP/5518/PCI_Dawn_sm.jpg
NVIDIA has developed a high-speed x16 graphics interconnect designed to evolve current PCI technology and address the increasing bandwidth demands of emerging graphics applications for multiple markets, including desktop PCs, mobile solutions, workstations, servers, and embedded communications systems.

A Winning Combination for PCI Express:
Watch the video on Intel, NVIDIA, and the PCI Express collaboration.

The graphics processing unit (GPU) has the largest bandwidth appetite of all PC subsystems, and from the start NVIDIA has been a key contributor to the PCI Express architecture, as both a developer and supporter.

NVIDIA is excited to help shape this next-generation specification to ensure that NVIDIA GPUs get the necessary throughput required to push the visual envelope for a seamless multimedia experience with cinematic-quality graphics at its core.

NVIDIA is a key PCI Express SIG member and contributor to the following PCI SIGs:

Graphics
Protocol
Electrical
Mechanical
NEWCARD
Cable
Mobile
System BIOS
Board Design
Software
Thermal
Bus Functional Model