Paul, existem muitos atalhos de teclado para alterar o seu brilho para cima e para baixo.
Um é o FN + X para ajustá-lo.
Além disso, tirado daqui: link
On most laptops, there are already shortcuts to change the brightness. For example:
On HP (and other models) is the Fn + F7 to key increase or Fn + F8 to decrease brightness.
On IBM ThinkPad, Fn + Home or Fn + End
Asus, Fn + F6 to increase, and Fn + F5 to decrease.
You can easily find these shortcuts just by looking on the keyboard. Brightness is often designated by a small sun with an arrow at the top or bottom. But sometimes we need that the proper driver is installed for these buttons work!
Eu não acho que você deveria ter atualizado.