- DX and DY control the screen positioning offset in physical units (not pixels)
- MAGH and MAGV define the relationship between physical units and pixels
- DW and [B]DH/[B] define the size of the visible screen sections in physical units (not pixels)
- The physical units are the VCK clock for horizontal axis and raster lines for the vertical axis

Diagram displaying the relationship among DISPLAY1/DISPLAY 2 GS Registers fields DX, DY, DW, DH, MAGH and MAGV
"Those six values are the component bit fields that together comprise the contents of a DISPLAYx register. Those are two of the main registers we patch to achieve proper scaling and centering of enforced GSM vmodes.
Into GSM, MAGH and MAGV are never directly controlled by the user, but are automatically adjusted for best possible rendering of a 'requested' vmode (requested by game or other software) into the physical vmode enforced by GSM (as specified by the user in the GUI).
DW and DH define the width and height of the physical vmode, with the units being HLines for the vertical axis and VCK clock periods for the horizontal axis. This relates to pixels by the following equations:
Width_in_pixels = (DW+1)/(MAGH+1);
Height_in_pixels = (DH+1)/(MAGV+1);
DX and DY define the physical offset of the top left screen corner, using similar units as DW and DH.
DX,DY are primarily used for screen centering, but due to the automatic adjustments of GSM the relationship between enforced and requested DW, DH pairs also has a very strong influence on the effective borders, though their influence is always symmetrical around the screen center."