New spec speeds data transports
Published: 09 Feb 2004 11:05 GMT
A new version of the HyperTransport specification comes out this week that will, ideally, boost 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 most current HyperTransport specification hits a maximum of 12.8 gigabytes per second while running at 800MHz.
Computers are amid 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 all the compatibility issues. As a result, these changes only occur every few years.
PCs containing PCI Express links, for instance, will start to show up in the second quarter. Initially, PCI Express will link the processor to the graphics chip, replacing the AGP link, but it will incrementally supplant existing connections between the processor and USB ports, now connected through PCI, 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 $5,000 (£2,706) to $40,000 a year, depending on the level of participation.








