On Wed, 21 Jan 2004, Doc Shipley wrote:
     The Sun Composite-Sync signal and the SGI
Composite-Sync signal
 aren't on the same pin, and most CS-capable monitors do it the Sun
 way.
   Pulling pin 10 disables CS from the SGI adapter and forces
 everything
 to SOG.
    I can verify this on Indy, Octane, Indigo2 Extreme and Impact, and
 IIRC, Indigo R3k models. 
 Do you know if and how the Apple 13W3-15 cable (Apple 590-0615-A)
 differs from the "SGI/Sub" version?  They look the same
 externally, but Apple is rather (in)famous for altering pinouts. 
   I dunno.  I've never seen either cable in the flesh.
        Doc