I'm not sure about the mono. That is some other type of signal, TTL or something. Never tried to use that TT mono option. With the crazydots I can exceed the 1280x960. That was my solution. Not a real good solution now though. Trying to find such a card is like triyng to find hens teeth.
Far as I know it does require an older monitor and the TT can detect it, otherwise its disabled in the desktop res setup dialog.