Windows 7 in-place upgrades can take hours
 

Microsoft may have made Windows 7's installation process faster than Vista's, but an in-place upgrade can still take a little while. Chris Hernandez of the Windows Deployment team has written up a blog post about tests conducted to benchmark the new operating system's upgrade performance, and the results are a little surprising.

For a "heavy user" with 125GB of user data, 40 installed applications, 15 "optional components," and modified settings, the upgrade can take 150 to 355 minutes, depending on the hardware—up to six hours, in other words. Meanwhile, a "super user" with 650GB of profile data can look forward to an upgrade time as high as 1220 minutes (over 20 hours) on a "mid-range" system with Vista x86. Ouch.

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