PC Parts and What They Do?

Last updated: 2021 Feb 9.
Hi. I’m thinking of building a PC for Blender.

I just wanna know what each part of a PC does for Blender?
Here’s what I found. Correct me if I’m wrong/add any missing parts:

----Single Thread CPU Performance----
Is good for:

  • viewport animation playing
  • modeling,
  • editing*
  • simulations etc,
  • Freestyle (but freestyle is slow)

*I found a post that says modeling, editing, but I’m not sure what the difference is. (Because you edit a mesh to model it, right?)

P.S. LANPR aka LineArt. Does it or will it use single-thread or multiple cores of CPU? Or will it use GPU? Or a combination of? Does anyone know?

----CPU In General----
Operations are calculated on CPU (like selecting or moving vertices)

----GPU Graphics Card(s)----

  • “Eevee is a GPU-only engine and that doesn’t run on multi-GPU configurations. Eevee supports bloom, ambient occlusion, depth of field, screen-space reflections, motion blur, volumetrics, and indirect light baking.”
  • faster viewport display, more vertices count
    ^“A PC with a powerful GPU can handle Millions of vertices and faces, but Consumer Notebooks cannot be used to get that performance.” [from a post on Nov, 2020]
  • for geometry selection (does this mean selecting objects, vertices, etc in the 3d viewport?)
  • viewport rendering (does this mean displaying objects in the 3d viewport? Or does this mean rendering images/animation to a file(s)?
  • overlays, and
  • Procedurally generated textures work better on GPU than CPU
  • you need ~1GB VRAM per 8 million TRIS PLUS ~ 1GB VRAM for other stuff (kernel, etc)
  • GPU rendering which is faster than CPU rendering (unless there’s an issue of some sort?)
    “GPU can assess RAM when it’s out of VRAM, but it slows it down, “out of VRAM” error happened on older version when CUDA didn’t supported GPU accessing RAM.”
    ! 4K monitors require stronger GPUs.
    o FPS Playback Benchmarks for various GPUs for Blender 2.91:
    https://techgage.com/article/blender-2-91-best-cpus-gpus-for-rendering-viewport/2/

Viewport Performance for RTX 3080
[https://www.youtube.com/watch?v=svGzdWQaqpc]

----RAM----

  • Not enough ram leads to blender crashing.
    Does anyone have an approximate “this much RAM is needed for a blend file with this many objects”?
    Also, do RAM and VRAM do different things in Blender? Like, if you have 64 GB RAM, but only 1GB VRAM, then will your blender crash?

----SSD----
Does an SSD only affect the time it takes to open Blender?
Or does it affect other things like render times or loading textures or anything to do with accessing owr writing files?

----Monitors----
1440p or 4K monitors require a more powerful GPU than a 1080p monitor
“since they have more pixels = more calculations for GPU
Just like rendering image in different resolutions.”
“A bigger framebuffer also takes more memory, though modern gpus shouldn’t have too much of a problem with that. Maybe edge cases.”

----OS Operating System----
Blender FPS playback in viewport is higher in Bodhi Linux and Zorin OS than in Windows 10.
(e.g. From 7.5 FPS to 15FPS in Solid Viewport on Blender 2.79 for 54k verts, after subsurf and mirror modifiers).

Let me know if this is correct, if it’s missing anything, etc.
Thanks.

Some links:
[https://www.cgdirector.com/best-computer-for-blender/#Eevee_Rendering]
[https://blender.stackexchange.com/questions/200599/gpu-function-in-blender]

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Displaying Viewport runs on GPU
Operations are calculated on CPU (like selecting or moving vertices)

What does this even mean?
Texture is a Texture, CPU is a CPU

It depends on GPU and CPU capabilities…

VRAM is GPU memory and used for GPU tasks
RAM is used by CPU
GPU can assess RAM when it’s out of VRAM, but it slows it down, “out of VRAM” error happened on older version when CUDA didn’t supported GPU accessing RAM.

Obviously since they have more pixels = more calculations for GPU
Just like rendering image in different resolutions.

Well obliviously if you have massive file it going to load faster from faster source…

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A bigger framebuffer also takes more memory, though modern gpus shouldn’t have too much of a problem with that. Maybe edge cases.