(Copied over from another thread, just to keep this information with this thread as well)
I have looked closely at the two IB-CRT boards that I have, and the documentation that comes with them.
The boards output a separate vertical and horizontal sync signal.
That means they are not sync on green.
From a link posted earlier in another thread...
http://en.wikipedia.org/wiki/Component_video_syncSeparate sync
Uses separate wires for horizontal and vertical synchronization. When used in RGB (i.e. VGA) connections, five separate signals are sent (Red, Green, Blue, Horz. Sync, Vert. Sync).
Sync-on-green (SOG)
Combines composite sync with the green signal in RGB. Only three signals are sent (Red, Green with Sync, Blue). This synchronization system is used in - among other applications - many systems by Silicon Graphics and Sun Microsystems through a DB13W3 connector.
The IB-CRT interface sends 3 separate signals, which are the green signal, the horizontal Sync, and the vertical sync. These are 3 signals out of the 'separate sync' definition above. It does not send red and blue, out of the five separate signals mentioned, as it only displays a green signal.
I have made a box to send that green signal being output from the IB-CRT board into the red and/or the blue input of the monitor, so that you can change the colour of the MPC display on the monitor. This box can disconnect the green signal from the monitor, and only send it to the red and/or the blue inputs of the monitor.
If it was sending a sync on green signal to a sync on green monitor, then it would not work when the green signal was disconnected from the green input to the monitor, and would not work when the green signal was being sent to the red and/or blue inputs instead of the green input of the monitor, but it does work, which means it is not sending a sync on green signal, and is using the separate horizontal and vertical sync signals that the IB-CRT is outputting.
I think that the real problem is in finding a monitor that will sync to the particular frequencies of the signal that the IB-CRT board is outputing.
I bought a second hand Acer LCD from a regular computer fair/sale. I took along my MPC with me and went from stall to stall, asking sellers if I could plug it into their monitors and see which ones worked, then bought one that did work.
Here is the IB-CRT Operator's Manual...

You can see that it outputs the green signal on pin 2, pin 1 and 3 would normally be red and blue signals, but these are not used as it only displays a green image on the external screen rather than a colour image.
You can also see that it outputs separate horizontal and vertical sync signals on pins 13 and 14.
If it was sync on green output, it would not have separate sync signals on pins 13 and 14, the sync would be included in the green signal.
I think the real problem is finding monitors that will sync to the 31.468 kHz horizontal and 60 Hz vertical sync signals that the IB-CRT board is outputting.
My Acer LCD screen actually reports that the signal is 29 kHz horizontal and 59 Hz vertical, in the info section of the onscreen menu. I would have to hook it up to an oscilliscope to get totally accurate measurements of what it is really putting out.