• PC World
• »Components

USB 2.0 vs. Firewire

I'm shopping for an external hard disk to back up several computers. I want a fast drive with a fast interface, so I'd like to add a USB 2.0 or FireWire card for the drive and the computers. Which should I choose? Which is faster?

Carm Lyman, public relations specialist, Lake Tahoe, California

You've correctly identified the two fastest interfaces for connecting external devices--and sensibly ruled out the poky USB 1.1 interface, which would be too slow for your application. Remember, though, that your immediate need for an external hard disk isn't the only factor in your decision. The whole idea behind external interfaces like USB and FireWire is to accommodate a wide range of devices, so which other ones you might want to attach should influence your choice as much as anything else.

USB 2.0 is a much newer spec than FireWire, and fewer devices currently support it. But its chief backer is Intel, which will be building support for USB 2.0 into all its computer chip sets. Other chip set vendors are behind it as well, which is why most new motherboards are shipping with USB 2.0 ports built in. This guarantees that manufacturers of digital cameras, camcorders, hard disks, scanners, CD-RW drives, and so on will build support into their devices. In addition, USB 2.0 ports can receive USB 1.1 devices. That's a fairly minor issue, since virtually all PCs four years old or less already have a USB 1.1 port, but it makes the transition to USB 2.0 much easier.

Having originated on the Macintosh, FireWire is typically an add-on for PCs. Nonetheless, by the time you read this, you'll still have a wider selection of FireWire than USB 2.0 devices on the market to choose from--especially among digital video camcorders, where FireWire appears to have established a permanent niche. And such companies as ATI and Creative Labs are beginning to build FireWire ports into their graphics cards and sound boards, respectively.

Finally, our performance tests confirm that if there's one thing you shouldn't worry about in comparing the two interfaces, it's speed. (See the " USB vs. FireWire" test report.) Although USB 2.0 supposedly supports throughput as high as 480 megabits per second versus FireWire's 400 mbps, FireWire actually turned out to be slightly faster. But these differences may flatten out over time as newer USB 2.0 devices are refined.

Our conclusion: If you want the widest compatibility with future devices, go with USB 2.0. If you're primarily interested in digital video, choose FireWire. Or as long as you're going to the trouble of adding an expansion card, why not buy one that supports both interfaces? At about $100 on the street, Adaptec's DuoConnect is a little pricey, but you get three USB 2.0 ports, three FireWire ports, a six-foot FireWire cable, and Sonic MyDVD 3 video editing software. Not a bad purchase if you want to be prepared for anything.

For either interface, the upgrade is simple. Turn off and unplug your PC. Use an antistatic wrist strap to prevent static damage while working inside your PC's case. Locate an empty PCI slot, and remove the metal slot cover. Gently insert the new card and fasten it down using the screw you removed earlier. Plug your PC back in and turn it on. Once Windows boots, it should detect the new card and prompt you to install drivers. Follow the manufacturer's directions for any software that came with the card. With the drivers installed, you should be able to start using your USB 2.0 or FireWire devices by plugging them into the new card.