Thank you very much Fiery!
(it's the OP, I simply forgot the credentials of my "old" account)
Would there be any way to prevent those reading errors from happening in the future? It still messes up the average value sadly.
By the way, by "video display driver" in point 3), you are refering to both, dedicated GFX drivers AND integrated GPU drivers [intel HD], if I got that correctly?
Again thank you very much for your detailed and quick response!
Regards