The next two years are going to see significant changes in the way that PCs are designed, according to Intel executives speaking here at this week's Intel Developer Forum.

At the heart of this change is an Intel initiative, codenamed Big Water, which has set out to determine how future PCs can be designed to incorporate recent and future advances in technology.

Intel is saying little about Big Water's technical specifications.

The firm has promised to reveal more details later this year and will release the finalised Big Water specification in 2003, in time for the first PCs based on the design to hit the market in 2004, according to Louis Burns, general manager and vice president of Intel's Desktop Platforms Group.

But some details of the initiative are clear. For starters, the Big Water design will rely heavily on PCI (peripheral component interconnect) Express technology, a draft serial input/output specification formerly known by its codename, 3GIO (third-generation I/O), and under review by the PCI-SIG (PCI Special Interest Group), the industry organisation set up to manage the PCI standard, Burns said.

PCI Express offers the benefit of faster data transfers between the components of a PC. It provides a communication channel of up to 200MBps (megabytes per second), close to twice that afforded by existing PCI technology, according to PCI-SIG. This increase is essential for future PCs to keep pace with advances in processor clock speeds, high-speed LANs and demand for greater graphics capabilities, it said.

Another characteristic of Big Water will be greater flexibility. During a keynote presentation at the IDF, Burns demonstrated how a Big Water PC would include add-in modules, based on PCI Express technology, that allow users to easily upgrade various PC components, such as a hard disk drive.

"Essentially, we're trying to show with Big Water a huge amount of flexibility," Burns said. "The concept of a single form factor, a single box, one size fits all, is clearly not what customers want."

Big Water designs will likely be smaller than many existing PCs and will be designed to be mounted in places where most users would hardly consider putting their current PCs, such as on a wall. "We think small form factors are a big play," Burns said.

In addition to faster data-transfer speeds and improved flexibility, the Big Water design will be set up to handle the increased levels of electromagnetic interference caused by faster microprocessors. Devices are currently available that can simulate the EM characteristics of a processor running at speeds up to 8GHz, allowing PC chassis designers to begin work on future PC designs capable of handling these EM levels, Burns said.

Other technical issues that will be addressed by the Big Water project include a more cost-effective power supply, better thermal characteristics and less noise, according to Burns.