How to force a tri-mode monitor to only vga?

[emuola]

In mame.ini, do I just add this line in the switchres core options:

monitor_specs0    31000.00-32000.00, 55-65, 0.33, 3.58, 1.75, 0.316, 0.063, 1.137, 0, 0, 576, 768

The modeline is the last one of these suitable ones:

NANAO MS-2930/MS-2931 (pyrojoe, thefooz, senorchris)
monitor_specs0    15450.00-16050.00, 55-65, 3.19, 4.75, 6.45, 0.191, 0.191, 1.164, 0, 0, 288, 448
monitor_specs1    23900.00-24900.00, 55-65, 2.87, 3.0, 4.44, 0.451, 0.164, 1.148, 0, 0, 480, 768
monitor_specs2    31000.00-32000.00, 55-65, 0.33, 3.58, 1.75, 0.316, 0.063, 1.137, 0, 0, 576, 768

Or is there something else to it also?

[Calamity]

In mame.ini, do I just add this line in the switchres core options:

monitor_specs0    31000.00-32000.00, 55-65, 0.33, 3.58, 1.75, 0.316, 0.063, 1.137, 0, 0, 576, 768

Yes, that's all you need to do. Make sure the rest of monitor_specs options are set to 'auto'.

[emuola]

In mame.ini, do I just add this line in the switchres core options:

monitor_specs0    31000.00-32000.00, 55-65, 0.33, 3.58, 1.75, 0.316, 0.063, 1.137, 0, 0, 576, 768

Yes, that's all you need to do. Make sure the rest of monitor_specs options are set to 'auto'.

Thank you Calamity once again