Well, when it comes to wear and tear on components I am a strong proponent of leaving the computer always on. Most of the wear on things like fans, disk drives, etc., come from spinning them up repeatedly. They last "almost forever" when perpetually on in my experience (at least if there's the occasional necessary vacuuming of the intake and output grates for the fans and the heatsink on the motherboard are done). I never sleep my laptops when they're not on battery power for this very reason.
I always kill the monitor when I'm not going to be using it for an extended period, though. Those are the power hogs, particularly on mobile hardware.
Edited by britechguy, 10 November 2015 - 06:51 PM.
Brian AKA Bri the Tech Guy (website in my user profile) - Windows 10 Home, 64-Bit, Version 1803, Build 17134
Memory is a crazy woman that hoards rags and throws away food.
~ Austin O'Malley