Hi there!

After having integrated drivers to Windows, the resolution changes automatically to 1024*768, making the billboard background being decentered to the top left corner.

I know that's absolutely not important, this is only a question of cosmetic.

If someone knows how to prevent resolution to change / to chose resolution to fit to the background / to fit the background to the resolution, please let me know.

Specify Screen resolution in WINNT.SIF
Its due to Drivers of Graphics. drivers are installed during the installtion and display adapter get detetect at 37 Min (installing devices phase) and resolution get changes.

Reference