If you’re up to it you may want to give the internals a good clean of the dust and debris buildup. A one inch paint brush and a can of canned air is all you need besides the needed tools to open the system up. Follow this guide [guide|41648] in addition there is a known issue with the backlight LEDs string loosing connection due to the Lead free solder chemistry used at this time. Here’s a deeper view into that issue [guide|175666] to verify the issue when it winks out place a flashlight against the screen at a sharp angle you should still see the faint image of your desktop and its icons. If you do then that points to the backlight either the LED strings or the backlight power logic.