If you’re having problems with performance and you suspect a service is to blame, the first place to look is at the list of third-party services, which are added by other programs and might be conflicting with another program or simply misbehaving. To see a concise list of third-party programs, use the Windows System Configuration utility, Msconfig.exe. Click the Services tab and select the Hide all Microsoft services checkbox at the bottom.

You can use the check boxes to the left of each service shown here to temporarily disable a service, then restart and see if the problem you noticed has gone away. During the course of researching this article, I discovered that the Intel Viiv service running on a Dell XPS 420 was acting up for a minute or so every time I started up. The symptoms only appeared when I tried to run a program that wanted to run with administrative rights; clicking the program icon appeared to do nothing, and not until a minute later did I get the UAC dialog box I was expecting. Disabling the Viiv service, which I wasn’t using, solved this problem.

You might be tempted to disable other services on the theory that you’re never going to use them. The Tablet PC Input Service, for example, is enabled by default even on a desktop system. It uses no CPU resources at all, and disabling it recovers a mere 36 KB of RAM. Regaining that RAM will make absolutely no noticeable difference in performance, but it also won’t hurt.

On the other hand, some services perform tasks you might not expect from their name. The Themes service, for example, runs the Aero user experience look and feel. If you disable it, you’ll switch back to the ugly 1998-style Windows Classic look.

In my experience, only three built-in services have a meaningful impact on performance on a properly configured Windows Vista system:

• Superfetch is Vista’s new and improved caching service. It keeps track of the programs you run most often and tries to preload them into unused memory (as a background process) so that they’re available in the cache when you need them. Superfetch really does work, cutting seconds off the load times for programs you use regularly. The trade-off is that Superfetch spends time and disk accesses managing itself. Some people dislike the chattering of the hard disk as Superfetch does its thing. If you’re one of them, you can disable Superfetch in the Services console as I show in the accompanying screenshot gallery.
• Windows Search is, for my money, Vista’s killer feature. For most people, it really is a time-saver. But if you don’t use it, or if you prefer a different indexing tool, you can disable it, or at least limit the amount of indexing it does. Doing so can reclaim a significant amount of RAM and disk space. I’ll offer advice on the best way to use and manage Windows Search in next week’s installment of this series.
• Windows Defender is Microsoft’s anti-spyware solution, which is enabled by default in every copy of Windows Vista. It runs as a service and can be particularly annoying when it does its daily scans for potentially unwanted software. To shut it down completely, open the Services console (Services.msc) and set the Windows Defender service startup type to Disabled. In my opinion, a better option is to tone down its aggressive scanning behavior: Open Windows Defender, click Tools, click Options, and then clear the Automatically scan my computer checkbox.

And that’s it. In my experience, those are the only three built-in services that have a measurable impact on performance. If someone tries to talk you into disabling a bunch of other services, ask them what you stand to gain. I’ll bet they can’t tell you.