If you disable pin 12 just remember you'll encounter a few minor issues:
A. If mono autodetection doesn't work and your video card outputs a color display it won't be like looking at a B&W TV... what you'll see is only a luminance representation of the green component. Red and blue elements will be completely dropped out. To get a sensible display you'll have to force the OS to render in grayscale
(Back in the DOS era there were programs that would hit the VGA registers directly and ignore the state of the sense lines. If you had a mono monitor, like I did, the result was most annoying.)
B. I remember reading a discussion somewhere speculating whether it could damage a video card to run with one or two of the analog color lines active but disconnected. (an old-fashioned VGA card supposedly shuts down red and blue when a mono monitors active.) I think the consensus was "probably not, but if you're really paranoid you could hang some resistance off them". Personally I wouldn't worry about it.
A. If mono autodetection doesn't work and your video card outputs a color display it won't be like looking at a B&W TV... what you'll see is only a luminance representation of the green component. Red and blue elements will be completely dropped out. To get a sensible display you'll have to force the OS to render in grayscale
(Back in the DOS era there were programs that would hit the VGA registers directly and ignore the state of the sense lines. If you had a mono monitor, like I did, the result was most annoying.)
B. I remember reading a discussion somewhere speculating whether it could damage a video card to run with one or two of the analog color lines active but disconnected. (an old-fashioned VGA card supposedly shuts down red and blue when a mono monitors active.) I think the consensus was "probably not, but if you're really paranoid you could hang some resistance off them". Personally I wouldn't worry about it.