I believe the licence restricts you to one installation per machine, so even if you can install both 32bit and 64bit versions in a dual boot arrangement I suspect you can only activate one of them. And that seems to be the case judging from a brief Google.

By the way, Photoshop CS3 is a 32bit application, so there's no advantage to running it under 64bit Vista.

£219 is a better price for Vista Ultimate than is £300+, but I'd still rather have another XP and £160 to spend on something useful.

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