Thank you so much Wayne for the schematics
It is much appreciated
When the monitor is cold , it makes a high pitched noise on low resolutions
also the size of the image changes "contracts" after it warms up , that's to say a "30 minute" the width and the lenght of the picture decreases by let's say "0.5 cm" more noticibly the width ....
do you have any clue where might be the fault ?