A clean install beats an upgrade

There is a new version of OS X out soon and Lion is to be replaced by Mountain Lion. Windows 7 will be replaced by Windows 8 later this year and Linux is updated so often it is hard to keep up. The question faced by users of each of these operating systems is whether to upgrade the version they are currently using or wipe the disk drive and perform a clean install.

In theory it should not make any difference whether you upgrade or install, but in practice it does. I have upgraded OS X on an old MacBook from Leopard to Snow Leopard to Lion. I also have a new MacBook with Lion and there are subtle differences here and there. There's something different about Mail, for example, and I keep meaning to run both Macs side by side and compare them. Maybe it is just down to configuration settings, but maybe not. It's not the only difference.

I also have Ubuntu Linux upgraded from either 9 or 10 to 11 and now 12.04. It works fine, but if I do a clean install of Ubuntu 12.04 (in VirtualBox) it is noticeably different. Some of the icons in the Launcher are different for a start, and there are other subtle differences. It is the same story with Windows upgrades.

In all cases I think the clean install version of the operating system is the best one. Perhaps it is compromises that are made when upgrading an old OS or it is an effort to upgrade the OS, but keep things the same as far as possible.

If at all possible, copy your documents, music, photos and videos to a USB drive, format the disk and install the new operating system on a clean disk. Then copy your files back. The disadvantage of this is that you lose any software you had installed. This is a problem if you cannot reinstall it. Freeware, open source and even some commercial software can be reinstalled though, and updating the OS is a good reason to update your software too. There may be new versions that take advantage of features in the new OS.