This question is an extension of this one.
My problem is my Aspeed video card (not a gpu) ends up dectecting and using the wrong video polarity that results in an a off bound video output along a resolution the screen doesn’t recognizes.
This happens both in Xorg and the kernel virtual console and with generic video drivers as well as the official deprecated Linux Aspeed drivers. 
It should be noted that I didn’t had this problem with that screen the last time I used vga output with an old agp Nvidia card 15 years ago.
Neverless, the more recent Windows based official driver doesn’t have this problem. 
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Based on the documentation,
how do I set the correct polarity or get the right video polarity to be detected correctly?
