An ATI Radeon HD 4890 graphics card may appear as an unknown device in Windows 7 after a fresh install of your operating system. This is because only built-in device drivers will be left on your computer, such as drivers for keyboard, mouse, and CD/DVD drive. On the other hand, peripherals such as an Ethernet card, network adapter, and video controller will be listed as unknown devices or problematic devices and will require re-installation of device drivers.

A video controller such as the ATI Radeon HD 4890 graphics card will be unusable without installing the required device driver. In this case, the computer will only use the Microsoft OpenGL driver (built-in Windows OS driver). This will result in slower or poorer graphics displays, and limited resolution options. To fix this, it is required to install the right driver for your graphics card, either from the installation CD or by downloading the latest version online. If you are not careful, you may end up installing a wrong or incompatible driver and cause even more problems and frustrations.

Here are the three practical steps you can take to fix this problem and avoid the ATI Radeon HD 4890 graphics card being listed as unknown device in your Windows 7 OS.

1. Confirm the Identity of Your Unknown Device

Before downloading the device drivers, you should confirm that the problematic unknown device is indeed the ATI Radeon HD 4890 card. This is very important, especially if there is more than one unknown device present in your PC's Device Manager. You can do this by checking the Vendor and Device IDs of your device:

  1. Click Windows Button
  2. Click Control Panel
  3. Click System and Security
  4. Click Device Manager
  5. Right-click the Unknown Device
  6. Click Properties
  7. Click Details
  8. Select Device Instance Path
  9. Look for VEN_**** and DEV_****. If it's Radeon HD 4890, from the alphanumeric data, you must have VEN_1002 (Vendor ID = 1002), DEV_9460 (Device ID = 9460)

2. Confirm the Type of Your Windows 7 (32-bit or 64-bit)

This is very important to avoid downloading incompatible device drivers.

  1. Click Windows button
  2. Enter “System” in the Search Box
  3. Click System
  4. Look for System type: It's either “32-bit Operating System” or “64-bit Operating System”

3. Download Process via AMD's Official Website

In the upper-right portion of the homepage, just under the “Supports and Drivers” tab, you will notice the portion with the phrase “Find a Driver.” Just point to that portion with your cursor and then the “Download Drivers” form will be provided. There are four boxes with drop-down options that you need to select from before you can download the right device drivers. You need to specify the category of your device in the first box, and since it is a graphics card, the right category is “Desktop Graphics.” The second box is labelled with “Product Line,” which requires specifying the series of the graphics card, in our case it's Radeon HD Series.

The “Product Model” will be specified in the third box, and the right selection is Radeon HD 48xxx Series PCIe. The last box is very vital, where you will specify the “OS type” to prevent incompatibility issues, and in the case of our example, it is 32-bit Windows 7. Clicking “View Results” will redirect you to the download page where you can choose to download AMD Catalyst Packages or undergo “Individual Downloads” and “Optional Downloads.” The Catalyst Software Suite is the package which includes other device drivers compatible with the Radeon HD 4890. In the Individual Downloads, you can choose to download the Display Driver alone, and additional downloads are available in the “Optional Downloads” tab. If you are not sure, the safest way is to download the complete package.

As a recap, let us review this 3-step process that will help you avoid unknown device problem in your Windows 7. First, before downloading the device driver for the ATI Radeon HD 4890 graphics card, you must ensure the identity (name and model) of your unknown device by using the ID's to prevent downloading wrong device drivers. Second, check the OS-type to avoid incompatibility issues. Third, be very cautious when choosing from options required for locating the right drivers on the manufacturer's website. Always have in mind to carefully read descriptions of downloadable files, for example: Catalyst Software Suite or Display Driver only.

Source by Steve Flores