GPU or not GPU

[WhoCanDo]

Hi all.

 

I'm looking at a new computer because I'm fed up with waiting 5min for a stair tread to render/refresh "Final Quality Renderworks".

 

While it is rendering, I am watching the Task Manager.

 

I have read articles from VW that say that the GPU is the priority, but in Task Manger, it's hardly doing anything.

 

The problem I see is maxing out the ram, and the CPU is running at 98%. My ram is doing a small amount of caching.

 

You can see my current computer specks in my footer.

 

If I'm going to get an upgrade, I think it should be a top of the range CPU and fast ram.

 

Why does VW suggest the GPU is the main component to aim at ?

[Pat Stanford]

It depends on your render mode.

 

Shaded runs on the GPU.

 

Hidden Line and Renderworks run on the CPU.

 

I think Redshift runs on the GPU on Windows and the CPU on Mac.

 

I am certain others will provide better suggestions.

 

Have you considered using Cloud Services to do the rendering? It might actually be slower, but at least you don't have to watch it run slowly and can do other work.

[WhoCanDo]

Thanks Pat.

 

I'm using "Final Quality Renderworks" rendering.

 

We are adding realistic pictures to our brochure.

 

As far as I am aware, cloud services only works with Sheet layers, and I'm using "Export to Image" with "Save Alpha Channel" to remove the background.

 

Unfortunately, the cloud services (or Sheet Layer) result leaves a lot of unwanted background pixels around the perimeter of the objects, giving a pour result at 300dpi.

 

The abrasive nosing is made of thousands of realistic cubes for a grit surface when viewed closer - for our close shots.

 

[rDesign]

21 minutes ago, WhoCanDo said:

The abrasive nosing is made of thousands of realistic cubes for a grit surface when viewed closer - for our close shots.

That certainly could be part of why it is slow to render. Instead of thousands of cubes, you could achieve a similar result with a displacement texture.

Edited April 16, 2025 by rDesign

[Jeff Prince]

13 hours ago, WhoCanDo said:

The abrasive nosing is made of thousands of realistic cubes for a grit surface when viewed closer - for our close shots.

@rDesign ‘s suggestion of a displacement map is what I would do.  If you have a closeup focusing on that surface and it is important to be graphically accurate, it would be best to delete everything else from the scene and save the closeup as a separate model.  That will sped things up quickly.

 

similarly, you could render just the yellow nosing and save it as a png.  Then, render the rest of the scene without the nosing.  Combine in a photo editor.  Sometimes that is actually faster when you are dealing with complex surfaces.

 

a final suggestion. Render a top view of just the nosing and use that as your texture.  You can also export the same view as a hidden line drawing to use as a displacement map by making the raised squares white and the floor black in a photo editor.  Now you will have an accurate representation of the material and a very fast way to render it.

[jmcewen]

The other option might be to back out of Final Quality Renderworks into a custom setting.  Every setting is turned up to "high"(I believe I read that somewhere-- PLEASE SOMEONE CORRECT ME IF I AM WRONG) in Final Quality, and you may not need all that.  You may be able to turn off grass,  and number of reflections and blurriness and speed things up a bit.  You also don't seem to have a lot of curves so you may be able to turn down curved geometry.  If you have modeled the thousands of tiny cubes, you also can turn down the displacement mapping because you have already done its job.

 

At the same time, I said I think that all the settings are on "high."  If there is something that really matters to you, you might be able to get higher quality results in Custom Renderworks by turning a setting or two up to "very high."

 

Displacement mapping especially can slow things down in some cases.  I agree with the others that replacing your modeled texture with a displacement mapped texture would be faster, but if you need exactly what you have and want to wash your hands of this, then turning it off entirely may be the way to go in this case.

 

Final quality is a default setting.  Playing with some sliders may give you a better result with far less render time.

Edited May 2, 2025 by jmcewen

[grant_PD]

Have you tried combining the thousands into 1 solid thing?  That makes a shorter list for the renderer to work through.  

Without looking at your settings,  I'm struggling to see how your render is "final quality," it kind of looks like OpenGl.  If that is the level of quality you're looking for, I think you could dial down a lot of settings to achieve a faster result.