Windows 7 installation query solved

Q I have a large external hard disk on which I wish to install Windows 7, rather than altering the present setup on my computer. Is it possible to do this and would you recommend it?

Martin Ansell

A While it is technically possible to do this, we would not recommend it. You can probably convince Windows 7 to install itself on your external hard disk, but it will be a tricky process, and even if you do so there are then three additional problems.

You will have to convince the computer to load Windows from the external disk, it will be slow and if you disconnect the external disk while Windows 7 is running, it will cause problems.

This is all because your external hard disk will be connected using a Firewire or USB connection. While both of these are fast enough for transferring files, they are not fast enough to run an operating system.

Windows constantly has to go back to the disk for various files while it is running, as well as using the disk for what is called virtual memory. Even if you tell it not to put virtual memory on the external disk, it will still be quite slow.

The disk on which your operating system is installed needs to be connected to the computer at all times. For a standard internal hard disk that is not a problem but an external one can be easily knocked or unplugged.

Finally, there is the matter of making Windows load from the external disk. It is possible to do this on most modern computers by changing the options in the Bios, although we cannot really help here as the instructions differ depending on the computer’s manufacturer.

If you do not want to overwrite your current version of Windows with Windows 7 you can install a second hard disk in your computer – assuming it’s a desktop model with a spare internal drive.

You can pick up a good-sized internal disk for less than £50 from any computer shop. A disk of 120GB will be more than large enough for most people. Then once it’s fitted you can install Windows 7 on that disk (internal hard disk connections are significantly faster than USB ones).

A simpler answer might be to use Microsoft’s Virtual PC software and run Windows 7 as a virtual PC. That way there’s no risk that it can cause problems to your installation of Windows and once you have evaluated it, you can upgrade fully.

It will be slower than a proper installation but less hassle than installing it on an external disk.

Baffled by jargon? See our free online jargon buster