Dell Inspiron AIO Screen dimming after waking up..

[technics100]

I have a Dell All in One 2310 machine, since upgrading to windows 10, when waking up from sleep the screen is dimmed. If I go to the bottom right corner the brightness is at 100%. I click the icon and it goes to 0%, gets brighter and I continue to click 25%, 50%, 75% and then 100% and it's back to normal.. which each click it gets brighter..

Anyone any ideas? Auto brightness etc is turned off..

 

[Nawty]

Is there an energy efficiency mode?

 

[technics100]

No, not that I can see.. it's like it's defaulting to the lowest setting and is grand after I bump it back up manually.. until the next sleep!!