Superwide display

[matti.salo]

I have an RPi3 and I'm trying to connect this display with HDMI from eBay:
HDMI DVI VGA LCD Controller Board With 14.9" LTA149B780F 1280X390 LCD Display
But what ever i try on config.txt, i cannot get that "weird" resolution to work.

Any help?

[aBUGSworstnightmare]

Do you have a data sheet? Is it working on another PC ie.? You're sure you have the right controller voard for it?