Problem with lag

I’m very new to 3D modeling and Blender, by very new I mean started maybe 2-3 hours ago. I was watching a youtube series from the account “Blender Guru” and on the 2nd part of this doughnut tutorial I learned about adding modifiers to my object (a torus). The modifiers I added were called a “Subdivision Surface” and “Wave”.

The problem is that when I go above a View of 3 in the subdivisions the fps drops drastically. At 3 it stays steady at 24fps, then at 4 it drops to around 10fps, then at 5 I see it around 2fps. Is this normal? I have a fairly new desktop PC I will post the specs below.

Operating System: Windows 10 Pro 64bit
Processor: Intel i7 7700k
RAM: 32 GB
Graphics Card: Nvidia Geforce 1070ti
Storage: Samsung 500gb SSD, and a 2TB hybrid disk drive

Blender is installed on the Solid State Drive.

It might just me being new and not understanding how sensitive Subdivision Surface is, but my gut tells me the problem isn’t how I am treating the program, but how the program is set up/how my graphics card and CPU are interacting with the program. I wanted to know if anyone had any idea how to resolve this issue or if it’s normal for it to be this way.

Thank you for your time, I tried searching for people with the same problem, but I was unable to find a solution (maybe it was there, but I didn’t see it or understand it)



untitled.blend (510 KB)

Use full interface screenshots to explain and prepare+upload a .blend when asking questions

It can be normal behaviour. The level doesn’t say much but how much geometry you have in total with the set subdivision levels. With models consisting of quadrilateral faces it adds 4 times more faces at each level, number_of_faces * 4^level in total.

Wrong modifier order. The wave animates the high resolution mesh which is slower. The subdivision surface modifier itself can slow down the viewport significantly and there are few things about that

  • You don’t actually need level 5 subdivision. The reason is because smooth shading is used to hide the edges, it’s not done with pure geometry (apart from 3d print models). For most things, level 2 is the targeted level, and rarely use above 3. The use of subdivision surfaces is usually planned in modeling and the targeted subdivision level is taken into account with the model density
  • The opensubdiv option on the modifier is for getting higher fps for animation purposes. You have to have and enable opensubdiv compute device in user preferences -> system. Bottom left corner in your screenshot
  • There’s a reason the modifier has view and render resolutions separately, which is to have lower one for viewport performance and higher for render time. Apart from the modifier itself, scene properties -> simplify can be used to manage subdivisions scene wide

this might be of interest
It also shows what Blender used to look like. Good times

Thank you so much, I was worried about my settings/hardware thinking that it might be normal to go into higher subdivisions. I mean I still am a little worried about why my PC wasn’t able to handle it as well, but if it’s not important or it’s rarely used I can probably work around it at least while I am still learning the fundamentals and learning the software. However I still want to be able to use my hardware to it’s full capacity (as I think everyone else would). Also moving the wave animation up did help the fps although it was still dropping. It’s still going pretty slow even using the opensubdiv option though. Thank you again for being so helpful, I really appreciate it.