Running an old Mac headless
From Wikistix
To run an old Apple Macintosh (LC, LC II/Performa 400, IIci, IIsi, Quadra 700, Quadra 900/950, Macintosh Duo Dock, and Duo MiniDock) headless, certain pins on the DA-15 (15 pin D-SUB, often incorrectly called a DB-15) need to be connected to force the computer into believing a monitor attached.
- pins 4 & 11: 640 x 480 monitor
- pins 4 & 10: 834 x 624 monitor
- pins 4, 10 & 11: 512 x 384 monitor
- pins 4, 7, 10 & 11: 1152 by 870 monitor
- pins 7 & 10: VGA monitor
