But other vendors are already offering PCs today that employ the legacy-free technologies that have come to market. For example, consider the Compaq Evo D510 e-PC (below). It's a largely legacy-free, extremely compact (4 inches by 10 inches by 12 inches, 10 pounds) sealed box that's small and light enough to hang on a wall instead of occupying floor or desk space. Its primary connectivity is provided by no fewer than six USB ports. There's no floppy, no legacy parallel or serial ports, and no slots inside the box; indeed, there's no real reason to open the box at all.

A related model, the D510 Ultra-slim desktop doesn't go quite as far, and isn't quite as small (3 inches by 12 inches by 13 inches, 11 pounds); it has five USB ports and one PCI connector inside, occupied by a modem. But both systems show one likely direction in legacy-free design: extremely compact form factors with little or no need for access inside the box.

Another possible outcome of legacy-free design may be true modular PCs whose components simply plug together, Lego-style, to meet a variety of computing needs. This will become increasingly possible with the advent of high-speed serial buses such as PCI Express and Serial ATA that will allow separate components to plug together with remarkable simplicity.

Even now, using the slower bus technology of today, some vendors are experimenting with exotic, modular form factors. For example, one largely legacy-free hybrid modular design is the "Modubility" PC (http://www.modubility.com/), whose central unit is a palm-sized, 8-ounce "information module," containing CPU, memory, hard drive, and operating system. This tiny central device uses wireless technology to connect to various "access modules" and display devices.

Indeed, as system designers are freed of the constraints of the past, we'll likely see radical PC designs that will not only be faster, smaller, and better than today's designs, but that will make the traditional beige-box PC seem positively antiquated. And I, for one, can't wait!

Fred Langa (fred@langa.com), the former editor in chief of Byte magazine, is an InformationWeek columnist.

---

Additional reading:

Legacy-Free/Legacy-Reduced Design
http://www.microsoft.com/ hwdev/platform/pcdesign/LR/default.asp

Legacy-Free Hardware And BIOS Requirements
http://www.microsoft.com/ hwdev/platform/PCdesign/LR/LfP.asp#BIOS

Legacy I/O Removal To Advance The PC Architecture
http://www.microsoft.com/ hwdev/archive/newPC/legacyIO.asp

Bus Technologies Overview
http://www.microsoft.com/ hwdev/bus/default.asp

ACPI/Power Management
http://www.microsoft.com/ hwdev/tech/onnow/default.asp

Fast Boot/Fast Resume Design
http://www.microsoft.com/hwdev/ platform/performance/fastboot/default.asp

IBM PC And AT History
http://www-1.ibm.com/ibm/ history/history/decade_1980.html

General Search: "Legacy Free"
http://www.google.com/ search?q=legacy+free

Antique Computer Virtual Museum
http://members.aol.com/ suprdave/classiccmp/ccidxa2z.htm