2004-06-21 PCI Express PC interconnect formerly known as 3GIO. Evolved from PCI and the physical interface of InfiniBand to a serial high bandwidth interface which will be used both as a PCI / AGP replacement and for chip to chip communications. Runs at 2.5 GHz and 0.8 V today, but will move to 5 GHz in PCI Express 2 in 2007-2008, and later to 10 GHz. Provides independent channels for each direction. Multiple bus widths are available:
- 1bit, x1: 250 MB/s (312 MB/s raw), 8 pins. PCI replacement
- 4bit, x4: 1 GB/s, 20 pins
- 8bit, x8: 2 GB/s, 40 pins
- 12bit, x12: ? pins
- 16bit, x16: 4 GB/s, 80 pins. Replacement for AGP and connects to the North Bridge
- 32bit, x32: ? pins
From PCISIG:
"PCI Express currently runs at 2.5Gtps, or 250MBps per lane in each direction, providing a total bandwidth of 16GBps in a 32-lane configuration. Future frequency increases will scale up total bandwidth to the limits of copper and significantly beyond that via other media without impacting any layers above the Physical Layer in the protocol stack."
Will also spawn a successor to the PCMCIA (PC-Card, CardBus) slot, 3GIO-M, Newcard or ExpressCard, which includes both PCI Express and USB 2.0 interfaces.2004-10-XX Nvidia NV45 NV40 with PCI-Express support, for the enthusiast segment. Performance identical, but adds PCI Express support. The Ultra version (> 500 MHz) is called NV45 U.