As an update to the maximum RAM supported for Windows 7, here’s my updated list I pulled from Microsoft’s website documented below on what the maximum memory is for the various Windows 8 editions.
Any 32bit version has a maximum memory of 4GB, but almost all systems you find now will be 64 bit, but just be sure. If it doesn’t specify 64bit, it’s most likelya 32bit Windows and you will be stuck with the maximum memory of 4GB which in todays’ standards is bare minimum.
If it’s 64 bit Windows, the maximum memory depends on the edition of Windows 8 as specified below and in the link below that.
Windows 8 – 128GB Maximum supported RAM memory
Windows 8 Professional – 512GB Maximum supported RAM memory
Windows 8 Enterprise – 512GB Maximum supported RAM memory