PC Design: The Shape of Things to Come?

Computerworld - One of the more intriguing aspects of PCI Express is the flexibility it gives manufacturers in redesigning the traditional PC box. With fewer circuits to design onto the motherboard, a 1X PCI Express slot less than 3 in. long and Newcard connectors (which replace today's PC Card slots) just 1.3 in. wide, vendors are experimenting with compact desktop designs that shed the traditional rectangular box shape without sacrificing expandability.

Hewlett-Packard's Chuck Stancil says the space-saving Newcard slots could become more common in desktops because they're less expensive to integrate than today's PC Cards, which have found a home mostly in laptops.

It's not just the shape of the PC that may change, manufacturers say. The traditional PC itself could disaggregate into a partitioned system that places noise- and heat-generating components away from the user while leaving the display, keyboard, mouse and removable storage on the desktop. "It's a serial technology that allows potentially split-system concepts," says PCI-SIG Chairman Tony Pierce.

HP recently showed a prototype, co-developed with Microsoft Corp., called the Athens PC. That unit uses another high-speed serial technology, USB 2.0, as the interconnect, but Stancil says HP is considering similar types of designs based on PCI Express. And HP isn't the only vendor willing to experiment. "It's something we're going to play with," says Brian Zucker, technology evangelist at Dell.

A PCI Express Main Logic Board The typical 1X PCI Express slot for desktop PCs will be 1 in. long vs. 3 in. for 32-bit PCI slots, require just four wires, and deliver more than twice the bandwidth. A graphics adapter card (shown in the fourth expansion slot) will use a 3.5-in. 16X slot. Fewer wires means fewer traces are needed on the motherboard, allowing for more compact designs. Source: Intel Corp.