Testing the minimum GPU requirement to run Krita smoothly under 4K

In this July, I asked a question about what kind of GPU Krita requires to run smoothly under 4K. I didn’t receive any reply at the time. Today I have done some rudimentary research. I will put my findings here, in case the information turn out to be useful.

My intention was to find the cheapest, easily available GPU that I can recommend to Krita artists who bought a modern pen display. It came from my following observation that:

  1. Pen displays are so much cheaper these days. Even entry-level models can sometimes have 4K resolution.
  2. Art students new to digital painting are more likely to choose a pen display or a iPad-like device as a starting point these days. An art teacher told me that basically no one in his class uses a traditional graphics tablet anymore.

Therefore, I think the time has come for us to get a clear idea of the kind of GPU Krita needs to run smoothly on a 4K display.

Test methods:

  1. radeontop was used on Archlinux (KDE Plasma 5.26) to monitor dGPU and VRAM usage.
  2. A Radeon Pro WX5100 was used as a bare minimum reference dGPU.
  3. A UHD770 on a Core i5-12500 with 2x16GB RAM was used to represent a typical modern desktop iGPU in the best case scenario.

For a single 4K display at 60Hz, color managed:

  1. The UHD770 had prevalent, noticeable slowdowns under 4K. But it was able to keep up a usable framerate in general. Noted that it could actually run Krita smoothly under 1080P, something that older iGPUs often struggled to do.
  2. 2GB VRAM was used by Krita + Desktop + 1 sRGB 8bit 10000x5000 20 Layers document.
  3. 6GB VRAM was used by running everyday tasks casually alongside with Krita, for hours, that (4) happened. It was the worst it could get.
  4. Some apps did not free up VRAM after they quit.
  5. Krita could rarely push GPU usage above 80% on the WX5100. A faster GPU like RX 590 did not improve Krita’s performance any further.

Also noted that:

  1. The RX 6400 is about 20% faster than the WX 5100 in general.
  2. The WX 5100 is about 20% faster than Intel Arc A380 in general.
  3. The UHD770 is the average of typical iGPUs that people get from a prebuild desktop PC. Laptops usually have better iGPUs, but not by much.

My conclusion is:

  1. 2022’s integrated GPUs: they are likely to be able to run Krita under 4K at a usable framerate. But they can’t provide a truly smooth experience.
  2. 2022’s entry-level discrete GPUs: AMD RX6400, Intel ARC A380 are likely to run Krita smoothly under 4K.
  3. VRAM size: Ideally 8GB. Less than that, and you might want to close other apps while running Krita to minimize slowdowns.
  4. We can teach people to restart their PC in case of slowdowns, for memory leaks can eat up their VRAMs.
8 Likes

Thank for this writeup and information. When buying a gpu it is always hard to answer questions. This will help us to point in right direction