I have a Mac Mini (latest model) hooked up via HDMI to my 55 inch TV. Here is my problem....I will have Chrome open with a number of tabs open (sorry, I do not like Safari) and after awhile...the display will begin to dim...even while I'm typing...etc. The only way to get the display to come back up is to switch to another tab and then it all comes back up. I have looked online....I cannot seem to see anything about this. I've been thru all the display settings....nothing I've tried has remedied this. I will say....I'm a PC user...so I'm not very familiar with how Mac things work. Be gentle with me!