But, if you don't, or can't, and have even a three-year-old PC, you may want to just stick with the Windows you've got.

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Well, this might be as good as time as any to give some serious thought to Windows -- specifically, whether you want to stick around for Win8, and whether you'd prefer using the new OS on a touchscreen.

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"There are also computers with Windows that stick, " Dyson said, to great cheers from the crowded audience floor.

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From there you can create a bootable USB stick or DVD to install at a later date, with your Windows license validated.

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The 80s and 90s saw them stick with Macs as being the premium product at a premium price to Windows based machines.

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