Computer spec moving up the ladder

3GIO, which Intel first mentioned a year ago and which gained broader support in August under a project code-named Arapahoe, governs how network cards, graphics cards and other devices are plugged into computers. The technology uses different hardware but the same software as the PCI (Peripheral Component Interconnect) standard universally used in PCs and servers today.

The Arapahoe Workgroup has completed the 3GIO draft version 1.0 specification and will now hand it for review to members of PCI-SIG, the special-interest group that governs PCI standards, said Bob Gregory, an Arapahoe Workgroup spokesman and director of strategic planning and initiatives for Intel's desktop products group.

The development is important for companies that want to get busy making the chips that will be needed to power 3GIO communications and for companies such as graphics card makers who could support the specification.

3GIO also has the advantage of being a more direct communication channel to memory and CPUs because it does not require "bridge" chips used by high-end versions of PCI.

Intel hopes 3GIO will arrive in desktop computers in the second half of 2003, Gregory said, though the more conservative server makers are expected to be slower in embracing the technology. Server makers typically take longer to adopt new technologies, as they're more concerned about potential problems and prefer to wait for any bugs to be worked out.

3GIO in servers has competition from a less radical alternative, PCI-X 2.0, a revamp of existing PCI technology that requires less of a hardware change.

PCI-X 2.0, like 3GIO, is governed by the PCI-SIG, but the group isn't advocating one technology or the other, said PCI-SIG President Roger Tipley.

"We're not going to set expectations for the market," Tipley said. "They both can handle anything we throw at it right now," including the coming 10-gigabit-per-second version of Ethernet.

PCI-X 2.0 and 3GIO are governed by a similar set of tech titans, including server makers Compaq Computer, IBM and Hewlett-Packard, as well as Intel and Microsoft. Dell Computer helps with 3GIO but not with PCI-X.

In the long term, 3GIO's use of high-speed "serial" connections will prevail over the "parallel bus" design of PCI and PCI-X, Gregory said.

The industry is in the midst of a shift to high-speed serial connections such as IEEE 1394, or "FireWire"; Serial ATA; and Serial-Attached SCSI. Parallel buses send streams of signals down parallel wires but are constrained by the difficulties of making sure all the signals are synchronized. Serial connections have fewer wires that transfer information faster, in part because the signals don't have to be synchronized.

"PCI-X is backwards-compatible, but you can't keep extending that forever," Gregory said. "There are challenges to running parallel buses that fast."

But the conservatism of server customers shouldn't be underestimated. "It's not easy to replace an existing industry standard," Insight 64 analyst Nathan Brookwood said in an earlier interview. At every juncture when examining whether to adopt a brand-new idea or to upgrade what's in place, "it always looks easier to do...just another two-year extension" of the existing technology, he said.

Dell, though, is crystal clear about its preference for 3GIO. Joe Sekel, a designer in the company's server architecture and technology strategy group, said the technology will arrive in servers in 2004. The advantages include lower cost and more data-transfer capacity, he said, adding that customers will have to make the jump at some point.

Furthermore, because the "Revo" design for plugging in 3GIO devices is simpler to use than the PCI card design, thin rack-mounted servers would be easier to design, Gregory said. Changing PCI cards is a tricky business, but changing 3GIO devices will be "brainless," as easy as swapping Nintendo game cartridges, he said.

The first version of PCI-X 2.0, initially called PCI-X DDR and now called PCI-X 266, will be able to transfer data at 2.1 gigabytes per second. PCI-X 533, formerly called PCI-X QDR, will work at 4.3 gigabytes per second.

The first version of 3GIO offers 0.5 gigabytes per second of data-transfer capacity but bumps up to 1, 2, 4 and 8 gigabytes per second with the use of more wires. In addition, the speed with which individual wires will transfer data will double, then quadruple, Gregory said.

Timing is key for Dell, Sekel said. "3GIO is going to be there before (PCI-X 533)," and perhaps even before PCI-X 266, he said. "I want to minimize transitions for our customers."