Hi,
i had problem with X58 chipset + Matrox Mystique 1060 4 MB. Graphics is fine, but there are some unwanted beeps even during boot, even before boot sequence start and sometimes after resolution change constant beep.

I never used Matrox cards for DOS too much, i dont have a manual, encounter someone similar or same problem? What it could be. During boot, there are only short beeps, but sometimes when i change resolution in Quake 1 and every time in Q2DOS i get constant beep i think that is from pc speaker.. With Q2DOS, when quit after resolution change and restart game with same resolution beep is gone. Could it be some error signal, like overheating or something like that on such old card?, i doubt it. Memory area conflict with pc speaker? IRQ conflict, but why it depends on resolution? Why non game beeps are only short and why its beeping right after start when card is still cold.
Im using this card only for DOS and for 2D in Linux sometimes (i dont trigger that beeping there yet), so i dont know if it would or would to do same thing with Windows, i have for them other cards and i dont want to mess with settings.
Update its Vesa related, if is vesa activated or tested from 640x480 up.