bob@coolgroups.com wrote:
> Any ideas as to how long PCI Express will be the dominant video
> bus type? Is its replacement on the horizon? I don't want to
> upgrade
> my mobo and then see PCI-E 2.0 everywhere a week later.
PCI Express 2.0 already exists :-)
It doubles the transfer rate of a single lane. I believe
it is a feature of Intel X38, for example. This is from the
X38 datasheet.
"PCI Express Interface
— Two x16 PCI Express ports
— Compatible with the PCI Express Base Specification, Revision 2.0
— Raw bit rate on data pins of 5 Gb/s resulting in a real
bandwidth per pair of 500 MB/s"
This is from Wikipedia:
http://en.wikipedia.org/wiki/PCI_Express
"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."
I don't know if there are any video cards that use it yet or not.
It isn't something I've been tracking.
Like SATA, this is supposed to be backward compatible. So the
lowest common denominator would pick the operating speed of
the interface. An X38, used with an existing video card, would
run at the "normal" PCI Express rate.
PCI Express will be dominant for some time. The reason is, it
is an "ideal" technology. Unidirectional point to point serial.
Using few pins per interface (i.e. per lane). Operating at as high a
frequency as FR4 PCB can allow (cheapest commodity substrate
for electronic devices). It might go out of favor, if some other
interconnect media became dominant (optical links - direct from
silicon to silicon). FR4 has been around for a long time, and
I don't see that changing soon, no matter how whizzy some of the
tech announcements get. The only way FR4 could be dislodged, is
if something cheaper comes along.
Paul
PCI Express 
Linear Mode
