By Michael Kanellos
Tuesday, February 10 2004 09:02 AM
URL: http://www.zdnetasia.com/news/hardware/0,39042972,39167747,00.htm

update A new version of the HyperTransport specification debuted Monday, raising hopes for increased performance in PCs and communications equipment over the next year.

When embodied in chips, HyperTransport 2.0 will be capable of transferring up to 22.4 gigabytes of data per second, according to Mario Cavalli, general manager of the HyperTransport Technology Consortium. There are three versions of the specification: the slowest runs at 1GHz, while the fastest churns (and hence transfers more aggregate data) at 1.4GHz.

The current HyperTransport specification hits a maximum of 12.8 gigabytes per second while running at 800MHz.

Computers are getting an overhaul when it comes to the links between internal components. Although steady improvements are regularly made to processor performance, speeding up data paths is a far trickier task because of a number of compatibility issues. As a result, these changes only occur every few years.

PCs containing PCI Express links, for instance, is expected to start showing up in the second quarter. Initially, PCI Express will link the processor to the graphics chip, replacing the AGP (Accelerated Graphics Port) link, but it will incrementally supplant existing connections between the processor and USB ports, now connected through PCI (Peripheral Component Interconnect), or the processor and main memory. These systems will also come with memory based on the DDR 2 specification.

HyperTransport is already used in Microsoft's Xbox consoles and in PCs containing Opteron and Athlon 64 chips from AMD, where it's one of main factors contributing to the increase in performance seen in these chips, according to many. In Opteron servers, HyperTransport links different processors to each other and to USB ports and other peripheral connectors.

Apple Computer began to incorporate HyperTransport into its computers when IBM came out with the PowerPC 970, which uses the protocol. Cisco Systems also uses it.

To pave the way for adoption, HyperTransport 2.0 will map to PCI Express, said Cavalli, which means that HyperTransport can be used with PCI Express compatible parts. The two technologies aren't necessarily direct competitors, but they can be used for the same functions. The new specification is also backward-compatible.

Cavalli would not comment on when companies will come out with products, but sources indicate that products could start coming out toward the end of the year.

The specification is royalty-free to members of the consortium. Membership, however, runs US$5,000 to US$40,000 a year, depending on the level of participation.