According to the manual, the SGI GDM-20D11 has minimum horizontal frequency of 48 khz so not sure if it would be usable with an Amiga other than with a video card. The Radius has an HD15 connector and is grayscale, not color. The others are analog displays, not digital, and have a 13W3 connector, not the standard VGA HD15. Looking at the specs, the Sun 447Z is the only one that can sync down to Amiga frequencies. You would need a 13W3 to HD15 adapter and a video card at 48+. They are multisync at frequencies above that - the SGI goes to 180.
