Usually a new version of Windows demands higher system requirements than the one before it. This wasn't the case with Windows 7, and it looks like it also won't be the case for Windows 8.
Microsoft yesterday demonstrated on stage at the Build event Windows 8 running on a three-year-old Lenovo S10 netbook, which packed an early model of the Intel Atom CPU and 1GB of RAM. Not only did it run Windows 8, but it ran it better than it could Windows 7.
The latest version of Windows 7 was demonstrated running with about 404 MB of RAM used for 32 processes. Windows 8 in its current, unfinished state is doing the same with about 281 MB and 29 processes.
This is not only good news for those who are still running on computers that are several years old, but it's also for those seeking a performance boost from the greater efficiency. Hopefully this will also translate into better power consumption numbers for notebook users.