Microsoft sets out Windows 8 tablet hardware requirements
So any Windows 8 tablet will have a minimum of 5 hardware buttons such as Power, Rotation Lock, Windows key, Volume up and Volume down. If the display of the tablets is to be considered, then Microsoft has set the minimum native resolution at 1366 x 768 at a depth of 32bits. The physical dimensions of the display panel must match the aspect ratio the native resolution. Also the display of the Windows 8 tablet or the convertible screens will need to be able to recognize five touch points, one for each finger.