Er no, W7 uses what it can. It will run happily on 1G of RAM but given more it'll use more. In fact it'll run quite well on 512mb so long as you don't use aero and only open one program at a time. Anything more and it starts hitting the swap too often.

In reply to a post by 12eason:

In fact it'll run quite well on 512mb so long as you don't use aero and only open one program at a time.

Might as well run DOS in that case.

Even Microsoft say you need a minimum of 1 gig. I wouldn't run it on less than 2. The more you can afford the better.

RAM is so cheap nowadays (again, suddenly, for no reason) that I'd go with 4 as a minimum. But that aside, you can install it on a system with 512mb, although I think you have to tweak something on the installer iirc. For me, it ran quite happily on a P4 with 512mb of RDRAM and an fx5200 with aero enabled, but if you pushed it too hard it would start killing the HD.