If you are a programmer - so much the worse ... you guessed rather than analyze.
It was enough to look sys.txt, and remember drivers to support HD ...
I wrote - Lotto - meaning guessing - if you feel offended - sorry.
On our forum there is a lot of people who are programmers - and yet (as you read posts) - no one is trying to solve the problems of type 2 + 2 = 4 with integrals - for what?
We write answers for users - who often do not really know "what's inside" - so you have to do this right clearly, specifically - but above all, effectively - because that's efficacy (IMO) expect.
PS. I think our discussion is finished, and the last answer for colleague @fretjes - solves his problems