With the release of the new Windows 8 , a lot of users are experiencing the following error message: “This PC doesn’t meet system requirements. If you want to install Windows 8, you may have to upgrade some of the hardware in this Computer.Your PC’s CPU isn’t Compatible with Windows 8” when trying to run Windows 8 CP setup (online installer). Here, I take for granted that you have already checked the minimum Windows 8 system requirements and that apparently, there is nothing else you can do. Most of the time such an error is triggered when the user is trying to install Windows 8 on old computer which doesn’t have the newest processors supporting Physical Address Extension (PAE), NX, and SSE2 where NX stands for “No Execute Bit”.
The reason that stands behind Microsoft’s choice to allow Windows 8 install on computers which have the NX feature in their processor can be read here. Basically, “…This is done for security reasons to ensure that malware defense features work reliably…”: However, if your processor does support NX feature, and still you doesn’t manage to install Windows 8, then maybe you have to turn the NX on from DOS! So, restart your computer and gain access to DOS. Look for “No execute bit” or equivalent XD (Execute Disable bit) in security settings and turn it on.