In search of the 15-minute Vista setup

In its road shows last year and earlier this year, Microsoft promised that you'd be able to install Windows Vista in as little as 15 minutes. But current beta builds aren't even close to that milestone. Where are the bottlenecks in the Vista setup process?

Yesterday, Microsoft released an updated build of Windows Vista, exclusively for technical beta testers. I’ve had the chance to install it on a half-dozen machines in the past 24 hours, and it’s given me a chance to look carefully at the new Windows setup process.

Presumably, the final setup process that Windows customers will see when Vista gets released will be a little smoother and a little faster than this beta. But recent builds have been complete enough to give a decent snapshot of what’s in store.

A clean installation from DVD using current builds takes about 30–45 minutes, depending on the oomph of the system on which it’s being installed. But an upgrade takes much longer – typically at least 90 minutes and sometimes several hours. Why so slow?

The answer lies in the new “staged install” process that Vista uses. Instead of copying files directly over an existing Windows installation, the new setup routine first copies files and settings from the old install, using a process that's similar to the Files and Settings Transfer Wizard in Windows XP. It then lays down a new base copy of Windows, adds drivers for any hardware devices that aren’t part of the base install, and finally migrates the settings and files into the new install. That multi-step process is probably safer and more likely to result in a stable instllation, but the extra steps at beginning and end mean that upgrades take a long time.

Clean installs, on the other hand, should go much more quickly. But the current builds don’t offer anything close to the 15-minute setup times that Microsoft promised in its road shows last year and earlier this year. Can Microsoft’s developers really cut setup time in half? We’ll just have to wait and see.