Introduction
USB 2.0 is a faster, more advanced enhancement of the so-called Universal Serial Bus, of which the 1.1 version is now standard on virtually all recent PCs and Macs. The new specification was finalized at WinHEC in April 2000 and released in Aug. 2000. Intel Corp. subsequently introduced the USB 2.0 Peripheral Integration Lab.
Hoping to forge a de facto standard, Intel said in Dec. 2000 that it would license its USB 2.0 enhanced host controller spec -- the interface between the host controller and its software driver -- on a royalty-free basis.
The USB 2.0 specification provides for a maximum data transfer rate of 480 Mbps --that's 40 times faster than the 1.1 spec, delivering performance comparable to that achieved by SCSI, IDE and FireWire (IEEE1394) devices. And, yes, USB 2.0 is -- theoretically, at least -- backward compatible with USB 1.1 devices. A typical USB 2.0 chipset can service four 12Mbps USB 1.1 hosts at the same time. Lucent, the developer of one such chipset, says this means that each port has its own USB 1.1 dedicated host for full and low-speed support.
Although it's hard to predict compatibility issues with every product on the market, we've heard of no instances where USB controllers have proven incompatible with older devices designed for the USB 1.1 standard. Still, it's worth summarizing some known issues with the 1.1 spec, as implemented by various manufacturers.
It's worth understanding which motherboard your system is based on -- and which USB Host Controller is onboard. It's unfortunate that PC buyers, who are often novice users, should have to deal with issues of this complexity, but... buyer beware! There are a number of potential snags that can occur with obscure components in certain types of PCs. For example, we've seen a number of audio products that claim proper functionality only results with systems based on PCI-to-USB controllers from Intel and ALi.
Perhaps more to the point, USB host controllers from Compaq, VIA Tech, Opti and SiS may not function reliably. In some cases (specifically, with the SiS7001 PCI to USB Open Host Controller), even the use of a USB mouse can cause audio interruptions. For example, you may be unable to play music CDs on your PC. Some problems may be solvable by the addition of an external, powered USB hub, some some are not. In short, if your PC is fitted with a USB host controller fro a company other than Intel or ALi, problems with USB audio or other USB devices may occur when using games or other software. Apparently, the underlying cause is the fact that the PC may not supply sufficient power to the USB port to reliably power the device.
Products
The first USB 2.0 controller card we've received here at PC Buyer's Guide is the Orange Micro OrangeUSB 2.0, a US$89 PCI card with four external USB 2.0 ports and one internal port. Although the drivers were still in "alpha" state when we installed the card in April 2001, they caused us no obvious problems. We've installed several updates since then -- again, with no trouble at all. The drivers support the full 480Mbps transfer rates and deliver all USB 2.0 and 1.1 features.
Indeed, the Windows 2000 USB 2.0 drivers supplied by the company seem to work very well under Windows XP and Windows 2000.
Orange Micro technicians cautioned that there may be power management glitches, but problems were not evident -- and that's more than we can say for a lot of shipping products. Our test machine (based on an Abit motherboard, with a PIII Coppermine and 256MB RAM) was able to hibernate and stand by without problems after installing the OrangeUSB 2.0 card and alpha drivers. We'll test the card and its drivers more fully as soon as a few USB 2.0 devices start showing up, but it looks as though driver support for Windows XP won't be a problem.
Microsoft in May 2001 backed down from its original stance and made USB2.0 support for Windows XP available as a downloadable update to the operating system.
Although Microsoft says USB 2.0 isn't supported under Windows 98 and Windows Me, some users have found drivers that work on these systems. Orange Micro has committed to releasing drivers for Windows 98, Windows Me, Windows 2000 and Mac OS X -- and the card already works as a standard USB 1.1 controller on USB-capable platforms. The company says it is doing a feasibility study on USB 2.0 support for earlier Mac OS versions. The Mac OS X beta drivers are currently very weak. They don't support USB 2.0 CDs, DVDs, Jaz, Orb drives or other types of storage media. We're hard-pressed to see ANY benefits to using this controller at all over the built-in USB 1.1 ports on the Mac platform, at least until support for high-speed storage devices is added.
40 times Faster
The OrangeUSB 2.0 card is distributed in Canada by EMJ. Orange Micro president Art Scotten was on hand at Comdex Canada West 2001 to demonstrate the "40 times faster" claims of the new specification. On one machine, he showed a QuickTime movie playing back from a USB 1.0-connected hard drive. Performance, in a word, was pathetic, with a frame rate we'd estimate around 4 or 5 frames per second. Next to it was a system with the new Orange Micro card connected to a prototype USB 2.0 drive, delivering smooth-as-silk playback of about 30 fps. (Note, however, that a typical DivX movie plays perfectly well on a USB 1.1-connected drive, so the Orange Micro demonstration was clearly illustrating a "worst case" issue, not a typical scenario.)
Scotten says he believes the new 2.0 spec's backwards compatibility with USB 1.0 will help speed the transition and feels that the 480 Mbps throughput of USB 2.0 will quickly make people forget the laggardly performance of the 12Mbps USB 1.0 spec.
He also showed us a combo card (shown in the images here) containing both external and internal USB 2.0 ports and external and internal FireWire ports. Now that's the card we want.
This section will contain information about other new USB2.0 products (and any problems encountered) as they emerge.
http://www.usb.org/developers/usb20/ has a listing of vendors and USB 2.0 products planned and currently available.
For more USB 2.0 info, See the USB 2.0 FAQ.
For Further Reading
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