You might think that all USB ports are the same, but they’re not. In the beginning, only USB 1.x was available. Sure, USB 1.x was a fine little port (easy to use and requiring no configuration) but only a few times faster than an old-fashioned serial connection. (To be honest, a FireWire device wipes the floor with the first generation of USB devices when it comes to speed. You can read more about FireWire shortly.)

Around the turn of the millennium, the list of peripherals that really required 400 Mbps of transfer speed was limited to digital video (DV) camcorders and external audio/visual (AV) hard drives used by video professionals. Today, that list has expanded:

  • Digital cameras: They produce images with bigger file sizes.

  • High-resolution scanners: These devices need to churn out images with 500MB of pixels (or, incredibly, more than that).

  • External, high-speed DVD and Blu-Ray recorders: Don’t even dream of recording a DVD over a USB 1.x connection.

  • MP3 players: These include my favorite, the Apple iPod.

Enter USB 2.0, currently the most common variety of USB connection. This generation of port ups the ante, delivering 480 Mbps, which handily tops the original FireWire specification, version A. And because it’s backward compatible with older USB 1.1 devices, you don’t have to start all over with your USB hardware, and cables will still work no matter which version of the port your PC uses. (Sometimes, change is not A Good Thing.)

Of course, only those peripherals that support the USB 2.0 standard can take advantage of the warp speed increase. The fastest USB standard, USB 3.0, offers yet another huge jump in raw speed, and is also backward compatible with USB 1.1 and 2.0 hardware. However, USB 3.0 devices may be somewhat more expensive than their USB 2.0 brethren.

(Naturally, if your PC supports only USB 2.0, there’s no reason to invest in USB 3.0 hardware — however, a USB 3.0 adapter card is a great inexpensive upgrade for your PC.)

If the external USB drive isn’t getting any power, and you have it plugged in, that drive might not be plugged into the wall socket for AC power — an easy troubleshooting task — but if you’re using a USB device that’s powered through the USB port itself, the problem might be more insidious.

Some USB ports don’t provide the full power support called for by the USB standard because they’re designed only for connecting mice, keyboards, and joysticks. As a workaround, try plugging that USB drive into another PC’s USB port to see whether it wakes up. If it does, try plugging it into another USB port in a different location on your PC.