Please explain how CPU and GPU interacts with the display

[Ryand123]

Obviously the whole point of a 5K display is to create incredibly sharp images. But does the CPU and/or GPU also effect the clarity of what you see or do they only determine speed?

It's kind of a dumb question....but I've never totally understood it. I think conventional wisdom says they don't impact sharpness but I suspect that may not be true. I had a 21.5 inch iMac with a 1920x1080 screen. I thought it looked pretty fuzzy/blurry. I have a desktop tower PC with a Dell 23 inch 1080 monitor--lower ppi than the Mac--yet it looks sharper to me. It also has an i7 4770K CPU and a GTX graphics card--650 I think? I'm thinking that must be the difference.

 

[paolo-]

They only determine speed. They calculate what goes on the screen and ship it to the screen. If they're too slow for what you're asking of them they just won't be able to ship the information at a steady pace to the screen but it won't become fuzzier.

The GPU is the one who's doing the talking to the screen. It also does computation, mainly for the things that will be displayed. It's really good at doing small repetitive tasks fast. The CPU on the other hand is the core of the computer. It's a general purpose computing device. It can handle all kinds of tasks and is also great at talking to the other parts of your computer (RAM, SSD, WiFi...).