As mentioned in the preceding section, not all hardware manufacturers make device driver updates available through Windows Update. Some hardware makers have very good relationships with Microsoft, and some don't.

What's a Device Driver?

A device driver is a piece of software that serves as a translator between the operating system and the hardware. For example, your video card, modem, sound card, scanner, and printer all require device drivers.

All hardware devices require device drivers, but it might seem otherwise on the surface because Windows provides its own generic device drivers for certain classes of hardware. For example, it supports CD drives, hard disks, keyboards, mice, and floppy disk drives in a generic way, and you do not need to install drivers for those devices. These types of devices have been around forever (okay, for at least 10 years or so, but in the computer world that's forever!), and their standards are very well established, to the point where a driver update for one of these devices would not be of much benefit.

On the other hand, some devices rely very heavily on device drivers provided by their manufacturers, and the manufacturers periodically release new versions of those drivers that add features or fix problems. The video card is a prime example. Today's computer games and graphics programs are constantly pushing the envelope in video performance, and it's very common for a video card manufacturer to come out with a driver update for an existing operating system every six months or so.

Is This Really Necessary?

Do you need to have the latest version of every driver? No, not really. In most cases it won't make much (or any) difference in your system's performance. Maybe you'll get a new tab on the device's Properties box, or maybe it will perform just a little bit better, but you probably won't see any miracles.

The main reason to seek out new drivers is to solve a problem or incompatibility. For example, suppose your computer is several years old and came with Windows XP preinstalled. You just bought a new computer game that doesn't play very well on your computer, and the documentation for the game suggests that you make sure you have the most recent version of your video card driver before contacting their technical support department.

Look for Signed Drivers

Windows XP likes to have a signed driver for every device. A signed driver has two things going for it:

• It's been tested and certified to work with Windows XP.
• It's been checked and found to be in the same condition in which it was released (that is, it has not been modified or tampered with).

It's possible to install an unsigned driver, but it's not recommended unless you have no other choice.

Let's back up a minute and talk about how driver signing came about. In earlier versions of Windows, one reason why they crashed so much, and why Microsoft seemed so powerless to fix the problem, was that a lot of the crashing was caused by poorly written or incompatible device drivers. Suppose you buy a cheap sound card, and it comes with a driver disk, but when you install the driver for it, your system starts crashing. Whose fault is that? Is it the sound card driver maker, for writing a bad driver? Probably. But who gets blamed for it? Microsoft does, because it's Windows that's crashing. There's nothing obvious that specifically points to the sound card driver as the source of error.

You can probably see where this is going. Microsoft got tired of being blamed for problems that were not its fault. So it developed this system of driver signing. For companies to release Windows XP-compatible drivers, they have to run them through a certification process controlled by Microsoft. If they pass, they get to be signed drivers. This ensures that if a device driver is installed in Windows, it's not going to cause problems.