Look past the simplistic Windows Experience IndexBy Ed Bott
Windows Vista doesn't have to be slow. In fact, most performance problems can be solved by fixing one or two bottlenecks. If you know where to look, that is.
Most Windows tips collections point you to this page but miss the real point. The numeric details shown here won't help you much, but two obscure links lead to sources of much more useful information. See the next several pages in this walkthrough for details about what you'll find and how you can use this hidden information.
For a much more detailed discussion of how to use Windows Vista's built-in utilities to find and fix performance problems, see Fixing Windows Vista, Part 3: Top Troubleshooting Tools.