Originally Posted by BottleRocket
Been doing some research on my next vid card, narrowed it down to the 8800GTS and the 8800GT. The GT is the newer card with PCIe 2.0. I'm already getting a motherboard that does not have PCIe 2.0. Will this card not work on this motherboard or can I still use it? The GT outperforms the GTS and uses less power, also is slim (1 slot, not 2) and lastly the GT is cheaper. I'd much rather order the GT, but again, can I use it?
PCI Express 2.0
PCI-SIG announced the availability of the PCI Express Base 2.0 specification on 15 January 2007. PCIe 2.0 doubles the bus standard's bandwidth from 2.5 Gbit/s to 5 Gbit/s, meaning a x32 connector can transfer data at up to 16 GB/s in each direction. PCIe 2.0 is still compatible with PCIe 1.1, so older cards will still be able to work in machines with this new version.
The PCI-SIG also said PCIe 2.0 also features improvements to the point-to-point data transfer protocol and its software architecture.
In June 2007 Intel released the specification of the P35 chipset which does not support PCIe 2.0 only PCIe 1.1. Some people may be confused by the P35 block diagram which states the Intel P35 has a PCIe x16 graphics link (8 GB/s) and 6 PCIe x1 links (500 MB/s each), for simple verification one can view the P965 block diagram which shows the same number of lanes and bandwidth but was released before PCIe 2.0 was finalized. Intel's first PCIe 2.0 capable chipset is the X38 and boards are already shipping from various vendors (Abit, Asus, Gigabyte) as of October 21, 2007. AMD starts supporting PCIe 2.0 from its RD700 chipset series. NVIDIA has revealed that the MCP72 will be their first PCIe 2.0 equipped chipset.
Q5: Then PCIe 2.0 must be backward compatible with PCIe 1.1 and 1.0?
A5: Yes. The PCIe Base 2.0 specification supports both the 2.5GT/s and 5GT/s signaling technologies. A device designed to the PCIe Base 2.0 specification may support 2.5GT/s, 5GT/s or both. However, a device designed to operate specifically at 5GT/s must also support 2.5GT/s signaling. The PCIe Base specification covers chip-to-chip topologies on the system board. For I/O extensibility across PCIe connectors, the Card Electromechanical (CEM) and ExpressModule™ specifications will also need to be updated, but this work will not impact mechanical compatibility of the slots, cards or modules. Currently, the PCI-SIG is defining the PCIe CEM 2.0 specification which has been released to members for review at v0.5. There are currently no plans to adapt the PCIe Mini CEM specification for the faster bit rate as the market need has not yet materialized.