Memory controllers and other things like onboard Lan, onboard Sata/RAID controllers, etc. depend on those to see those things work. Your display is usually an onboard as well as sound too.
When you start seeing problems come up and wonder why look at seeing those go on.
For looking at the desktop and web browsing only you can ignore seeing them go on. But once you start using other hardwares... "what's wrong?" ddaaaa.... Besides video drivers/software and sound I usually see those go on before anything else.
