Cycles Incompatible with AMD Vega on Mac?

I have a new 2017 iMac pro 10 cores 64 GB Radeon RX Vega 64 GPU. Cycles won’t use gnu, resulting in crashesafter BVH build. Is there a solution to this or am I stuck with cpu rendering?

signal boosting this question, as I just jumped on a Black Friday deal for a Vega 64, which in general was shown to benchmark quite well in cycles.

I’ve got plugged into my 2018 MacBook Pro via a Razer core x egpu enclosure. cycles doesn’t crash for me, however the Vega 64 is actually 2 times SLOWER than the 560x inside the MacBook Pro. I’ve since come across a bug report talking about egpu+macos+cycles issues, but if you’re having issues with an internal version of your card in the iMac, I’m curious if its more broadly a Vega + macOS issue?

Can any other Vega Mac users chime in? (do many of us even exist??)

blender acceleration was a major factor in my own purchase. I’d be sad if it doesn’t turn out to work. :frowning:

As @brecht has mentioned here, developers don’t currently have any egpus to test with so unless someone loans one to a developer I’m not sure there is much that will happen on that front. I suppose it would have to be a developer with access to a mac while at it.

Damn that’s a huge drag, I think it’s mostly MacOS drivers not being up to par. I have a 2012 iMac and I had to stop using GPU rendering because it’s no longer stable. Might work better on a previous OS.

I also thought that, according to Apple, This iMac pro was “made for realtime 3D…etc.” and so would be disappointed if cycles doesn’t work.

Does anyone know if running windows 10 on parallels, VM ware or Boot camp with MacOS would bypass this problem?

More than likely. Especially with boot camp which is basically just a dual boot setup. The VM Ware and parallels options would need IOMMU support which I’m not familiar enough with those to know if they support it or not.

As I understand you, your saying there is a good chance it will work. I thought so as well so I’m going to try it. If nothing else, there is blender software for Windows and not Mac that looks interesting.

Well I can confirm that the Dual-AMD GPU’s in the (still) current Mac Pro seem to work fine. Tested with yesterday’s 2.8 beta build. I had them render out some of the blender demo scenes.

Yes, there is no reason I can think of why dual booting/boot camp wouldn’t work, however I haven’t owned a mac in over 5 years now and can’t test. Nor do I plan to ever own a mac again(just don’t need it for anything special/specific to it).

@thomas_p would you mind sharing your bmw27 benchmark results? also are you on Mojave or an earlier OS?

there seem to be a number of factors that are influencing amd gpu performance for me:

-the Vega 64 egpu is worst when final rendering tiles. viewport rendering is less slow (although certainly still below the capabilities of the card). also turning on progressive rendering for final renders brings the speed in line with viewport rendering.

-the internal amd 560x dgpu does not exhibit the same issue when final rendering. I’m not sure if this is an internal vs external gpu issue, or driver differences between the specific gpu models.

-with viewport rendering, the Vega 64 is a bit slower than the cpu for larger viewport resolutions, but becomes faster as the resolution is lowered.

somewhat good news: with a bootcamp windows install, the Vega 64 performs as expected for cycles gpu rendering (bmw27 render in under 2 minutes). however, sorting the drivers for the egpu under bootcamp gets quite dicey. macOS Mojave apparently made things worse, as well as my particular situation of having an internal amd card on the MacBook Pro. the key is to get the windows installation all set up, then delete the amd driver installed for the internal gpu, and only then plug in the egpu which will download its own drivers without conflict. also I think the egpu will only accelerate an external display plugged directly into the graphics card.

Their marketing department got you…


Yeah 'll run that benchmark, will get back to you with some numbers.
And I’m on 10.13.6 (High Sierra).

Edit: I got 10:48.24 in the bmw27gpu file - that does not look right to me when compared against

Each D500 Firepro should be in the ballpark of a mid-7-series Geforce and there’s two of them. Render comes out fine though, headlights included.

yeah my little foray into windows bootcamp today made me realize how poorly gpu’s play with blender in macOS.

even the supposedly weak 560x built into the MacBook Pro can do the bmw benchmark in ~8 minutes in windows, compared to ~30 minutes in macOS.

I do still greatly prefer macOS for general use, but I can’t deny that graphics performance is just miles ahead in windows. The bootcamp + egpu combo in theory I guess gives the best of both worlds, except apple had to go and even make that difficult by not extending their egpu support to bootcamp officially. the whole thing feels a bit like a house of cards.

Well I don’t use bootcamp but I just ran the same scene in a build from around the same time on my Windows box, equipped with a GTX 1070. finished in 1:52 minutes.

It’s a bit hard to find performance numbers on the Apple-specific Firepro cards but according to this: the 1070 has an Open-CL score of around 150 000 vs a single D500, which is listed at 70 000.

So I’m figuring if properly utilized the dual setup should render the scene on the GPU’s in a little over 2 minutes… give or take.

Cycles works allright here, although Cycles macOS GPU support is not quite as good as NVidia support. I guess that’s mainly due to Apple’s crippled OpenCL support, favouring Metal.

The one thing I’m really looking forward to is a bug fix of Cycles rendering random black buckets when using GPU + Denoiser (check the comments in the thread).

If you want to get the most out of your AMD GPU on Mac, be sure to give AMD’s Radeon ProRender a try. It’s not available yet for Blender 2.8 though, but will be soon now that the beta stage has commenced.

in windows my vega 64 gets a geekbench opencl score of 177,000, vs 122,000 in macos mojave.

and in cycles its literally over a 3x performance increase.

as one outlier to all this, for some reason luxmark, which is an opencl benchmark specifically devoted to path tracing, for some inexplicable reason performs better on macos. the vega 64 reliably gets 28,000 on the ‘luxball’ benchmark, while windows gets more like 24,000.

@Metin_Seven i definitely tried out prorender on macos when i started seeing all these issues in cycles. its hard to do a 1:1 comparison, but i tried doing their automated material conversion on the bmw scene, and then set the sample count to 1225 to match the cycles benchmark. it took 2-3 minutes on macos which isn’t bad, but they also appear to be using metal which gives them a leg up. also their viewport rendering was erroring out for me, but i checked their forums and it seems this might just be a recently introduced bug.

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ProRender still has some growing pains, but I love the development team’s consideration for macOS users. Indeed, they’re using Metal, and the render engine is optimized for AMD GPUs, while Cycles seems to lean towards NVidia GPUs and Windows OS.

I found out that blender says the GPU is incompatible.

Does anyone know whether a .blend is interchangeable between windows and Mac?

It’s not a conscious choice. It’s just that nVidia has historically maintained the most stable compute environment with CUDA while Apple has in the mean while eschewed nVidia products for AMD, who have historically struggled with complex compute kernels with OpenCL. And now that OpenCL has finally more or less started working for Cycles, it’s been deprecated by Apple. It’s just bad luck.

Advanced open source projects that don’t have the backing of a self-interested, affluent corporation just tend to move very slowly as far as backends of all kinds are concerned.

Of course it is.