Despite lots of innovation with SuperFetch and ReadyBoost, Windows Vista wasn’t popular. In fact, many users avoided upgrading from Windows XP to Vista altogether. Though the operating system was the first version of Windows with 3D animation, and it offered many new features, it didn’t deliver enough compelling reasons to replace XP, which can now be considered really mature (if not over the hill).

Indexing updates could be retrofitted to Windows XP, and Vista turned out to be more hungry for resources than previous Windows versions. Windows 7, however, has been out for a few weeks, and feedback has generally been great. We decided to revisit our first look at testing these two operating systems head-to-head and directly compare Windows Vista and Windows 7, to see if the reported benefits are really noticeable.

What is Performance at the OS Level?

Most people think of application performance when they talk about performance in general. However, the operating system plays a major role in the process chain that creates everyday computing experiences. The OS is what switches a processor between power-saving and fast operating states (or even intermediate active states that determine performance in Intel's Turbo Boost mode via P-states). The OS, or to be more precise its dispatcher, distributes threads across available processor resources, and Windows 7 is more aggressive about using thread headroom for the sake of performance.

However, performance also has to be defined by the user experience during ordinary operating system actions, such as system bootup, standby, application launching, hibernation, or shutdown. If the OS were a bit quicker on applications but consumed several minutes during start-up or shutdown, you’d probably want to ditch it. Hence our second round of testing not only includes benchmarks and application tests but also a look at these everyday operations.