| The Hardware of the PC does not let me access to any monitor configuration.
| It seems that every thing is automatic (It is a recent Asus Motherboard).

Normally, any PC to Monitor adjustments will be in the Display settings or some such.  Someone more knowledgeable could even tell you some of the advance stuff in config files, monitor profile, and such.  The monitor itself should have a "Menu" button or access to a menu.  Owner's manual would tell you how to access the menu.  It is here that you may find a setting which could help you.