Tried various scrambling distance values but changes in render time are minimal.
It looks like a bug, the fireflies really shouldnāt be there too. Can you please provide a file and the steps to reproduce? About the learning, I spoke about it because you touched that value. Default is 0 and in the image itās at 1.
your set up is quite really unusual too, why did you choose three different cards ?
Anyway, it definitely look like a bug and until now, I only rarely needed more than a day to fix a bug I created. I just need more than images to identify the reason and fix it. By the way, the bug here is already fixed in the 2.8 beta builds.
Cycles only sees it as CUDA cores. Here the results:
Hi, I struggle today with the new tool, too.
After some hours I am more familar with the setup.
Start without denoiser and use the E-Cycles presets āQuick Settingsā from fastest.
Set samples the same in Cycles and compare quality and render time, then switch on denoiser and so forth.
I got first 0-30% speedup but now I come close to the x 1.6 or more performance boost.
Cheers, mib
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I am uploading the blend file to Wetransfer for you.
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How to reset quick settings presets values? Because when I choose one preset and then change a parameter it seems to replace the original value. So when I select a preset again it contains my values.
Where is the blender dev bug tracker for this multi gpu bug u were speaking about ? Iām curious to see if anyone take this seriously or if Nothing will be done for years
Hi Mathieu.
Again iām very confused about releases and changes. Currently thereās 3 versions in Gunroad (single GPU, multi GPU and abril Beta) and i have no idea about the diference between those and is quite impossible to keep track of those changes only by this thread with lots of posts by day. It would be nice to keep a text file in the folder with the versions descriptions, and release logs and a better name convention about those releases.
Your programming skills are outstanding but we need some love in the organization and documentation part also 
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I have no idea about what you talked about āblender dev bug trackerā.
Iāve rendered it with vanilla blender 2.8 and e-cycle 2019.3 version , those didnāt utilize multi gpu. Mathieu said it was a bug for months.
The bug wasnāt problem rendering BMW scene. Renderfarm worked so fast. But It didnāt for my scene.
I was so shocked to hear that multigpu bug had not been fixed āfor monthsā. Does Blender foundation render movies with single GPU?? or They use CPU renderfarm?
And in April, E-cycle multi gpu version released, I tried it and render time was what it should be.
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I must let you know that now it seems to be working. What i did is use the presets and change a bit to my needs. Before selecting a preset it looks like e-cycles was bugged or not enabled at all.
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Hi to everyone,
I will answer to each one separatetly later, but if you only get like 30% speedup out of the box, itās a bug and I need a real bug report like on developer.blender.org (your hardware, OS, graphic card model, drivers, file and steps to reproduce).
At least the time I and Tibor from Boostclock and other too report are just opening the file and rendering.
Kind Regards,
Mat
Hmm, thatās strange, I have to save the preset with the same name to overwrite it, will have a look again.
The preset system seems really buggy anyway, I tried to use the official one for sampling on the classroom scene and it does nothing (using buildbots), but on BMW it worksā¦
Hi Vitor,
sorry, I didnāt had time to do the changelog, I do the doc, fix the reported bugs and do a proper changelog. Regarding the stable release, the single_gpu is for single gpu and the multi_gpu is the same, plus a fix for multi GPU denoising (for a bug which is in official buildbots, just not so visible because Cycles is slower. But the fix can also bring other problem (none known yet, but still) so I offer both as single gpu user donāt need it anyway.
Short version for the beta:
- it has the multi-gpu fix, so the April release will have one build for all normally.
- it has the scrambling distance patch, will allows to render up to 40% faster (on top of existing speedup) and also reduces noise at low values, but may give artifacts in some lightning conditions. Theory animations uses it, so I think itās still safe to use it. It seems this float slider is a bit hard to use, so Iāll replace it with presets I think. It is set at 0.02 in this video:
- It uses half the memory when denoising with all passes (transmission and SSS included).
- It has the latest AI denoiser addon, which can now regenerate the tree with new settings in one click, so much easier to use.
Edit: I added the changelog to the product page, will update it regularly now 
Hi Mib,
do you have multiple GPUs? I didnāt port the multi-gpu fix to Linux yet, Iāll compile the new april beta for Linux too this WE. In the mean time, did you try on Windows? I know @stephen_leger uses the Linux version and he also had problems with speed at the beginning and itās now solved. Maybe you can also ask him? You can also PM me with files to discuss more in depth on specific scenarios.
Cheers,
Mat
Some of you had problems with Gumroad yesterday, I guess due to the high traffic. If you experience this kind of issue, please email [email protected] . I let the coupon for one day more active.
Hi, no single (Lowend) GTX 760 but I fixed all issues with performance copying preset settings to Linux. Not all settings are reachable on Linux atm. but I am not in hurry.
I know you are a speed fan but may you remember a patch to add some wait states to the GPU to donĀ“t block your system completely during render?
I cant find it yet at developer.blender.org.
I can render in Octane and surf the internet with some limitations without slow down render time. May a few % less.
It would be nice to have a switch for it, may GPU load High/Low or something.
Thank you for the support and for E-Cycles, mib
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At least on windows, the experience is smooth connecting. What I do is to connect my screen to the iGPU to have the discrete GPU completely free for rendering. But Iāll have a look to this switch. If you find the exact differential number, it would be helpful to get it faster.
Is the cpu rendering faster with E-Cycles?