There are a few options to get Windows 7 on a computer system. Many users will purchase a computer system that is already coming pre-installed with Windows 7. Those that bought a computer with Windows Vista or are running a computer system with that operating system or even Windows XP have some options. The options for turning a Windows XP system to Windows Vista is quite clear: Backup the data and perform a clean install.
Windows Vista users on the other hand can either do a clean install of Windows 7 or upgrade to Windows 7 from within the operating system. A recent Technet post by Chris Hernandez describes some tests that were performed with upgrades from Windows Vista to Windows 7. Microsoft has created three typical computer systems and user types for the test:
Medium user (user data: 70 Gigabytes, 20 installed applications)
Heavy user (user data: 125 Gigabytes, 40 installed applications)
Super user (user data: 650 Gigabytes, 20 installed applications)
low-end hardware (AMD Athlon 64 Processor, 1GB computer memory)
mid-range hardware (AMD Athlon 64 X2 Dual Core Processor, 2GB computer memory)
high-end hardware (Intel Core 2 Quad CPU, 4GB computer memory)
The full specs for the systems and users can be found at the blog post. Microsoft has then tested the upgrade performance in all possible scenarios plus three scenarios with clean user profiles (that is after installation of Windows Vista without any application installations or data additions). Below are the two results images, one for 32-bit upgrades and one for 64-bit upgrades.
The profile/system column combines a specific user scenario with one of the three computer systems. Upgrading a clean Vista SP1 64-bit installation to Windows 7 on a high end computer system took 30 minutes while the upgrade from a super user system on the same computer system took more than 545 minutes. Values are even higher for 32-bit updates of Vista SP1 to Windows 7, the highest being 1214 minutes to update a super user system on mid range hardware to Windows 7. That’s more than 20 hours and a user performing this operating might consider doing a clean install instead to save valuable time.
Our last poll indicates that 66% of all users who participated in the poll plan to do a clean install of Windows 7 while 30 plan on performing an upgrade from a previous Windows installation.
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