ATI graphics card

I’m trying to get cycles to use my ATI Radeon HD 5670 graphics card (I’m on an iMac).

Ok, so I go to “User Preferences”, click the “System” tab, and listed under “Compute Device” I can pick between “None” and “OpenCL”. I choose the latter, and “ATI Radeon HD 5670” is selected in the dropdown menu by default.

I go to the render tab, and can’t find the option to enable GPU rendering…
But I do find a menu that lets me pick between “supported” and “experimental” feature sets. When I pick the latter, a new dropdown appears with “GPU compute” selected. I do so.


My renders don’t work at all now (see image).

The render doesn’t even begin (it’s stopped at .18 seconds).
Am I to assume that ATI Radeon HD 5670 graphic cards aren’t supported by cycles … or am I just doing it wrong? If they aren’t, will they be supported in the future?

Is it working if you set it to None (so it is the CPU that computer) ?

Yes, the CPU rendering works.

Sooo … anyone know what’s going on?

Are you using an official version of Blender or a build from
As far as I know you’re clicking the right options and you have the right hardware (Radeon 5xxx or above).
To be sure, also check if you have the latest graphics drivers with the OpenCL driver.

OpenCL is not supported in Cycles yet even with the current 12.3 public drivers. CUDA works but OpenCL takes a while to compile on beta versions of the CCC. Of course as I am writing this I am downloading the 12.4 CCC and as I understand, they work with a little fudging, so I will let you know in a while.

Update: Since installing the 12.4 CCC and waiting for it to build the kernals for the first time, OpenCL does work, but only for flat diffuse shading (mix shaders don’t work) and you need to set the background color of the world to black so you don’t get a rainbow effect. Also environments don’t work. Basically you just need to upgrade to 12.4 for your CCC on your card, but you can only get pretty much flat renders at this point in time. I can say that it is one hell of a speed boost though.

Also make sure you are using a current Blender build. I was using the 2.63 release for this test.

Mix shaders work, not as they should, but they do look interesting.

2000 samples on an ati 6950 2gig; took around 4 minutes.

.png file saved with alpha:

.png file saved with no alpha:

You also might want to try a mingw64 build from, that builds bvh quicker due to different compiler; it also renders faster than normal builds. It’s still at the testing stage so save often if you use it always, but you could use a mingw64 build for rendering only. I do. :slight_smile:

Hi, thanks everyone for the info!
I am a complete n00b at this stuff and you might need to speak to me like I’m five years old.

Yes, I am using the most current release of Blender from the official site. 2.63.

So am I to understand that

  1. Cycles does not properly support OpenCL
  2. I should get a rendered output (albeit an ugly one)

Because I get no render whatsoever. No image. I don’t see it build the BVH or anything like that. Nothing.

Incidentally, I don’t understand any of those acronyms you’re using. What’s CCC? What’s CUDA? I don’t even know what OpenCL is. I’m guessing it’s the language used by my GPU?

How do I know if my graphics card and OpenCL drivers are up to date? If they aren’t, how do I update them?

Again, thank you!

Catalyst Control Center = CCC, or AMD’s driver and settings suite that has OpenCL bundled with it (the latest version I do believe or 1.2). Since you are on a Mac, I don’t know where to find this, so I’m not much help, but if you find it, you can upgrade directly from the CCC or you can go to AMD’s website ( and find your download and instructions for installation there. The latest CCC is version 12.4.

Don’t let the fact that OpenCL is not working quite that well yet discourage you. There are some people working on this outside the main development, and Brecht has it on his list of to dos, but later on in the development phase, so us AMD users have to wait a bit, but early performance tests show a lot of promise for AMD cards and OpenCL.

Ok cool. Thank you so much for all the info! I’ll look for Catalyst Control Center and I’ll likely be able to figure the rest out.

That’s awesome they’re working on it. Do you have any idea what kind of timeline they have in mind for the OpenCL support, or is this like one of those projects that will happen on its own time? Is there a development thread somewhere?