[robespierre]

They weren't. Early ones were but by the time of the nice ones - Octane-ish ? 1995 or so ? those were multi-synch.

From Reputable Systems' list of SGI monitors (http://shiftleft.com/mirrors/www.reputab...itors.html), it's apparent that only early displays like the CM2086 and GDM1950 are fixed frequency. These monitors were made in the 1980s. By the 1990s, superb displays like the 20D11 were available with a wide sync range including stereo modes at 150 fields/sec (and it has its own wireless remote). It does not synchronize below 48 kHz, because why would you want to?

Be careful about online information; I found sites calling the GDM20D11 a "fixed frequency" monitor despite that it's multisync. From PC users' perspective, anything that doesn't support MS-DOS 3.1 at 31.778 kHz VGA scan rate, must be "fixed frequency". There were special graphics adapters made for that market that used pixel-doubling to mimic VGA modes at higher output frequencies, to adapt MS-DOS PCs to workstation monitors.

Another sorry tale of PC users dragging the world back into the 1970s (with the 8086, character-cell video, and especially disco lights).

Also, I don't know any real argument to support why these old PROMs are superior to modern PC Firmware ... lighting