SOLUTION FOUND! I have a MacBook pro with the same issue. I found connecting and external monitor or TV with the HDMI cable corrects the issue. Then I purchased a CompuLab Display Emulaor on Amazon for $8.50. It's a small dongle you connect to your HDMI port. It fools the laptop into believing it has an external monitor connected. Better than an $1100.00 board. I put the link below. https://www.amazon.com/gp/product/B00FLZXGJ6/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
P.S. I tried all of the solutions out there and none of them worked for me.
Best Wishes to you all,
Port