I have been looking to buy a 17 inch full hd TN monitor for a PC and found that such a thing is basically nonexistent (at least in Europe).
So I did some online research and found out that it is fairly simple to just buy a laptop panel online and order a compatible controller board with an HDMI output and use it as an external monitor. At first, everything went smooth, parts arrived (B173HW02 V.1 panel specific controller), installation was straightforward, panel worked fine.

There is only one thing I find very annoying and don't quite understand: On my laptop or my pc, I can regulate the brightness of the screen through software or special keys on the keyboard, which alter the intensity/brightness of the screen's backlight.
When using the panel with the controller, however, it seems the backlight brightness can't be changed at all. There is a brightness and contrast option included on the controller board menu, but it just seems to change colors on the software level, which produces terrible results once you turn it up or down too far.

So my question is: I don't understand the technical issue here, from searching the web it almost seems these controller boards generally seem to be unable to control the backlight brightness, is this correct? Is there a solution? I have watched 3 video tutorials by different people so far, but they all stop at the point where the panel displays an image and skip any sort of calibration.