For years, PC Cards have been the preferred means of connecting high-bandwidth peripherals to notebooks and other portables. Now, they're getting a makeover: Today's credit card-like format is giving way to a smaller, faster, and more desktop-friendly format called ExpressCard.
All ExpressCard modules are nearly 3 inches long--about a third of an inch shorter than today's CardBus PC Cards--and two-tenths of an inch thick, the same as a CardBus PC Card. ExpressCard modules come in two widths: The ExpressCard/34 is only 1.33 inches (or 34 millimeters) wide, and looks roughly like an oversized stick of gum. The ExpressCard/54, in contrast, is a little over 2 inches (or 54mm) wide, the same as a CardBus card. At the plug end, a corner of the ExpressCard/54 is cut out, leaving a 34mm tongue with the same connector as the ExpressCard/34. ExpressCard slots will come in both widths as well, but both will have the same connector--and neither slot will accept CardBus cards.
Members of the PCMCIA (Personal Computer Memory Card International Association)--the trade group responsible for PC Card standards--introduced the first ExpressCard modules in 2004 in part to meet PC industry demands for smaller PC Cards for today's shrinking portables.
Another goal was to expand the PC Card's use to desktops by abandoning the requirement for a special I/O system for PC Cards: Instead, ExpressCard modules (the slots in the host PC) can interface directly with USB 2.0 and PCI Express buses found in virtually all recent PCs (ExpressCard vendors can choose which bus their product will hook up to). This makes supporting ExpressCard modules a lot less expensive than supporting CardBus PC Cards.
Last, but not least, the ExpressCard standard will accommodate scalable serial interfaces (PCI Express and USB 2.0) rather than the parallel PCI interface and will require a reduced number of signals to effect transfers. ExpressCard peripherals should begin appearing in stores later this year.
We tried out two preproduction ExpressCards and their CardBus counterparts. In our tests, we didn't notice much difference in speed between the ExpressCard and CardBus versions of AboCom's Gigabit Ethernet PC Cards.
But in informal use, AVerMedia's AVerTV Express Card TV tuner did seem to produce cleaner, smoother off-air broadcasts than the AVerTV CardBus. Both of these ExpressCards were the 54mm variety; PCMCIA expects the larger format will predominate for peripherals that need the additional width--micro drives and CompactFlash card readers, for example.
On retail shelves currently, AboCom's CardBus product costs about US$50; the company expects the ExpressCard to cost between US$79 and US$80. AVerMedia's AVerTV Express Card 54 costs US$100.
Widespread desktop adoption of ExpressCard isn't expected anytime soon, but the transition to ExpressCard on the notebook side has already begun: More and more new laptops, such as HP's Pavilion Zd8000 series, Toshiba's Tecra A4 and M3 series, and Fujitsu's Lifebook E8000 and N3500 series, are shipping with both CardBus and ExpressCard slots. PCMCIA officials expect that next year, 70 percent of new notebooks will ship with ExpressCard slots--and no CardBus slots.