How do computer graphic cards work?


I don’t understand how a better graphic car can make games smoother, or just how they work in general

In: 2

A CPU is mostly good at doing linear tasks very fast, and a GPU is mostly good at doing many things at the same time.

Games involve the drawing and animation of a lot of 3D models and textures, which is where the GPU really gets to shine.

A better GPU has more processor cores, and processor cores that are faster, allowing it to draw more things more easily, which allows a game to look better and run at higher framerates which make it look smoother.

A computer, as we know it. Is best described as a “general purpose” computer. It can do A LOT of different things, but none of them super well. It’s more of a versatile machine than it is a dedicated peace of equipment.

When you start to look at very specialized use cases we can make a better computer that only does this one thing really well than we can if we task our general use computer to this special task.

If you want a computer to do nothing but calculate a large biology simulation, the kind that might take days or months to run to completion. Then the best way to get that done is with special hardware that’s custom built to do just that one thing really, really well. Then you might be able to do it in days or weeks instead of months.

That’s basically what a GPU is. It’s an entire computer by itself (it has it’s own processors, and it’s own memory). But it’s not a general use computer, it’s a computer that ONLY does calculations relating to 3d graphics and displaying them on the computer screen. It’s custom built do to only this one thing, but do it really well.

If you could somehow ask a GPU to do something like handle your networking traffic, it would be really bad at it because that’s not what it’s designed to do. On the other hand, your normal computer can handle network traffic no problem.

But you could go out and buy a special computer that JUST does network traffic and does it really well, better than your general use computer can. Those computers are mostly sold by networking equipment manufacturers.

A GPU makes a game smoother because it’s much better at calculating all of the graphics things that need to get done. So it can do 60 frames worth of those calculations every second where’s if your general use computer was doing that it might only be able to do 20 frames of calculations per second.

Graphics card is essentially a second computer inside your computer – with it’s own processor (GPU) and its own RAM. When you start a game – a part of the code gets loaded into GPU, after that CPU and GPU split the work, each doing their own part. GPU mostly calculates colors for each dot on your screen, for each video frame.

Graphics card can be better in two ways: faster processor (GPU), or more video RAM.

Faster GPU does more work in the same time. That means:

* You can have more fine-grained picture (more dots on the screen – higher resolution), or more video frames (higher FPS – more “fluent” movements)
* You can have more objects on screen (far away objects won’t be cut off)
* It can spend more calculation on every dot – better lighting, more reflections/shadows, better translucent materials (glass, water, etc), more moving light sources.

Bigger VRAM means more space for video data:

* Bigger textures – more details on close up pictures.
* More textures – more different objects on screen.