The device’s high-resolution running Windows 8.1 allow increasing the number of tiles displayed by increasing density, leading, for example, if RT Surface to display an additional row of tiles on the Start screen. The setting is present by displaying the Settings Charm.
The setting is present by displaying Charm Settings (Windows key + L) and pressing the link “Tiles”. If the device’s resolution allows the setting “Show More Tiles” is present. The screenshot below is made Surface RT setting enabled and can see column 4 tiles Medium S.
Note that this setting affects portrait display mode. The Surface RT number of rows changed from 6 to 8 vertical crosswise.