Thank you MilesAhead for your tips.
The program you showed doesn't work for me, I adapted it for the command Attrib but I didn't succeed, however your tips about "drag & drop files" brought me to compose this line:

for %%A in (%*) do (attrib +a %%A)

"Drag & drop" files and the program works now. I hope to further develop it for my needs.

there's often a separate brightness slider for video overlay windows

-ayryq (June 05, 2015, 07:38 AM)

I think you have hit the target.
No, I haven't the item "overlay". I believe it's just what I need.

Now I will try to update the driver.

might be worth reading through the newegg reviews?

-tomos (June 05, 2015, 06:03 AM)

No, in that page there are data only. I'd like to read instead some comments from users who have/had my same graphic card (or my same motherboard). I am trying to understand if the drawback I reported is due to that graphic card.