News & Trends: USB--The Sequel

These days, hot-swappable, self-powered Universal Serial Bus ports are standard on nearly all PCs. But with its leisurely data transfer rate of just 12 megabits per second, today's USB 1.1 standard is painfully slow for such demanding, bandwidth-hungry peripherals as external hard drives and CD-RW drives.

But a next-generation version, dubbed USB 2.0 or High-Speed USB, promises transfer rates of up to 480 mbps--fast enough to edge out the principal competition, 400-mbps IEEE 1394 (aka FireWire or I.Link) ports. You can also plug USB 1.1 devices into a USB 2.0 port (though you won't obtain the faster speed). We looked at one of the first shipping USB 2.0 devices, Addonics' 8X/4X/24X Pocket CD-RW drive, and found a clear performance boost (see the test report).

We tested the Addonics drive in two ways: with a standard, built-in USB 1.1 port; and with a USB 2.0 port that we installed on the same PC using Orange Micro's $110 OrangeLink+ USB 2.0/FireWire adapter card.

In our CD-R tests with USB 1.1, the Pocket CD-RW drive's write speed topped out at about 4.7 mbps (4X), consistent with other external USB 1.1 drives (the bus reaches its maximum 12 mbps speed only in bursts, not as sustained throughput). Through the USB 2.0 port, however, write speeds reached the drive's maximum of 8X, or about 9.4 mbps. (The first devices that will fully exploit USB 2.0's bandwidth are hard drives, but they weren't available in time for our testing.)

USB 2.0 still has a way to go. First, it lacks the major operating system support that its predecessor enjoys. Even IEEE 1394 has support in Windows 98, Me, and 2000 and in the Mac OS. Also, computer makers are not yet building USB 2.0 ports into PCs.

In contrast, IEEE 1394 is a common option for most PCs (and is standard in Apple and Sony systems). Moreover, 1394 is commonly found on consumer electronics and doesn't require a PC; all USB devices do. Finally, 1394 will speed up to 800 mbps by early 2002.

But don't count USB 2.0 out. Microsoft has announced that it will offer downloadable USB 2.0 drivers for Windows 2000 and for the upcoming Windows XP operating system. Linux support for USB 2.0 should come in the first half of 2002.

Silicon behemoth Intel currently provides space for a USB 2.0 controller chip on its Pentium 4 motherboards, and Gateway has announced that it will put the chips in some PCs beginning this fall. Intel and Acer Labs plan to put USB 2.0 into at least some chip sets by mid-2002; Via Technologies, on the other hand, will add IEEE 1394 support to its chip sets before turning to USB 2.0. AMD says it will support USB 2.0, but not how or when.

With USB 2.0-capable hard drives and CD-RW, DVD-RAM, DVD-RW, and DVD-R drives coming from several vendors, USB 2.0 may become a standard feature on PCs in the next year or so. But for now, IEEE 1394 remains the better choice because it supports far more devices, especially digital video camcorders.

SUMMARY

Addonics: 8X/4X/24X Pocket CD-RW Pricey, petite drive adds USB 2.0 support. Street price: $389

SUMMARY

Orange Micro: OrangeLink+ PCI card adds USB 2.0 and IEEE 1394 to PCs. Street price: $110