GTX 1080 slow rendering - Cycles

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1

Hi folks,
i have problem. I bought the GTX 1080 (before i used only 1070). It’s very strange, but 1080 is roughly 30% slower rendering than my older card 1070.
How is it possible??? :eek:

Times:
1070: 1:52
1080: 2:23

Thank you!

2

Yup. That’s how :eyebrowlift:

You’re most welcome.

3

can you explain why ?
or you don’t get the 1080

thanks
happy bl

4

Might be something to do with the cards architecture (though they both seem to use Pascal)

I remember when i still had a 560ti and it rendered faster in cycles compared to my my 680.

5

How big is your scene?
What Blender version?
Is your card assigned as CUDA device in System?
Is Cycles set to render using GPU?
If you are on Win10, check in Task Manager while rendering, is GPU utilization at 100%?
What render tiles are you using?
Can you provide a blend file?

etc. etc.

6

In this benchmark: https://docs.google.com/spreadsheets/d/1rybGWiISHtgaUI-E_DIOM0wf6DW5UG1-p1ooizHimUI/edit?ts=56d095bd#gid=0
BMW scene: faster 1070
Classroom scene: much faster 1080
I do not understand it :slight_smile:

Blender latest 79a, win10 x64, i7 4790k, 16GB RAM

7

Thats because of the architecture differences between the 5xx and 6xx series… the 1070 and 1080 are the same architecture so the 1080 should be faster.

8

Are both GPUs installed in the same machine or two different machines with the same configuration.

If you are using win10, the card driving the monitors will be significantly impacted by rendering. Make the 1070 the card driving the monitors and restart your computer and re benchmark.

9

Hi,
same results with monitors on 1070

10

I’ve tried several benchmarks. Interestingly, sometimes it is faster 1080, sometimes it is faster 1070. It depends on the type of scene.

11

http://gpu.userbenchmark.com/Compare/Nvidia-GTX-1080-vs-Nvidia-GTX-1070/3603vs3609

There is a link that breaks the two side by side down rather well and thoroughly. I don’t see why you aren’t getting a slight improvement using the 1080 vs the 1070. How is your power supply (although if you are running the 1070 the 80 requires no different) and is the clocking set differently between the 1080 and the 1070 by factory?

12

Hi and thank you,
1080: ASUS ROG STRIX GAMING GeForce GTX 1080 OC DirectCU III 8GB

1070: GIGABYTE GeForce GTX 1070 G1 Gaming

The newer card has a higher clock. For example, 4K video editing has improved dramatically with the GTX1080 (Magix Vegas 15).
In Octane C4D, 1080 is slightly faster.