Troubleshooting unknown devices in Windows can be an arduous task. This will normally occur after a reinstall of Windows, and quite frequently can be resolved through a quick process of elimination. Newer versions of Windows typically will not have this problem, but Windows 98, Windows ME and Windows XP will quickly list a piece of hardware as an Unknown Device in the Control Panel if it doesn’t have a driver for it.
If you come across a rogue component in the Device Manager, the very first thing you should do is unplug any external devices one at a time and see if the problem goes away. Doing this will help you quickly be able to identify the problem. But if the unknown device is still referenced, you should quickly take an inventory of the hardware installed and match it up with entries that are listed in the device Manager. If the sound, graphics, network card and other components are all listed, then the problem likely resides on the motherboard. You will need to open the case and take a look at the PCI slots and see if there are any extra cards located there that do not have entries, such as a 56k modem that was installed and forgotten about years ago.
If you find a card that is no longer used, simply remove it from the computer and be done with it. If you realize this card is worthy of keeping, such as a network adapter or expensive SCSI controller card, then you will need to find a way to determine what it is based on the FCC markings printer on the card. The success rate of this is sometimes quite poor, but if you feel the card is worth salvaging, this process might be worth the time. Once you identify the part, you can then easily track down the software driver for it. Visit the FCC ID Search
Using Software to Identify Unknown Devices
There are also software applications that can be run to find information on Unknown devices listed in the Device Manager. A technician should have something along these lines in their toolbag for those instances where a user has lost all of their driver disks. Unknown Devices–the program–has been around for years and is used to identify troublesome unknown hardware. Find it here at Halfdone.com.