How to support low-end gpu's with Unreal?

Development Platform & Builds Debugging, Optimization, & Profiling
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1

I have two low end GPUs that are in my group of testing machines.
One is an ATI Radeon HD 3870 and the other is a Intel HD Graphics 4600.

I understand that these are low end gpu’s. However, they can run other AAA games like Dark Souls 2, Dota 2, LoL, Skyrim, Fallout 4, etc.

However, when I create a BLANK UE4 scene that is rendering absolutely nothing my FPS hovers between 28 - 30 (on the Radeon HD 3870 with only 512MB of vram).

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I can obviously see that the GPU is the bottleneck. But why would it be under heavy load when I’m not rendering anything?

What would the GPU be doing that takes this much time? It has nothing to render…

This is just a test because with my real project I am getting lower than expected performance and would like to understand what I can do to optimize.

Also, I hope the only graphics quality setting solution that we have isn’t to make everything extremely blurry?

I love UE and I know all the devs have insane gpu’s but come on…

Edit:
I have been looking at it with ProfileGPU to try and see what is going on.
Here is the output.

So, I disabled TranslucentLightingVolume with the following r.TranslucentLightingVolume 0. However, that caused StandardDeferredLighting to jump up to 32.64ms.

The last “Downsample” also seems way to high a lot of the time. For example, I’ve seen 9 - 15ms frames.
I’m not entirely sure how the downsampling works. But would love to find out.

2

Is that data from clicking play in the editor or standalone?

That’s the first thing I can think of. The editor adds a huge overhead on everything.

3

It is from a standalone. I’m adding some ProfileGPU information to the post now.

5

I don’t even have the sky sphere, light, etc. My scene is literally blank and just renders black. Which is one of the main reasons I was surprised. Seems odd that it would take more GPU power to render black pixels. Regardless, this is very useful information. I will keep playing around with the settings and ProfileGPU. I appreciate you help :slight_smile:

7

Hallo , pls am running on a 2Gb Nvidea GT 750. Pls i need clarification as to whether or not UE4 can run okay on my laptop?

Thanks