I'm hoping that OpenCL programming is supported on the ATI Radeon HD 5770/80 on a Mac Pro (4,1 in my case). Anybody have direct experience?

I'm only interested in the cards as compute engines, not really as displays, so a purchase decision here depends on the answer. My code runs fine on the default Nvidia chipset (GeForce GT 120) and on the GT 330 on my Macbook Pro, but the Radeon ought to be able to hit much higher gigaflops ratings....

Anybody gotten, say, the Galaxies openCL demo code running on the Radeon cards?

ATI Radeon HD 5770 Graphics Upgrade Kit for Mac Pro (Mid 2010)

ATI Radeon HD 5770 Graphics Upgrade Kit for Mac Pro (Mid 2010)

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2 Answers from the Community

  • Answer

    OpenCL is supported. However, you will notice a significant performance drop between the 5770 under Mac OS X (at least, 10.6.7) vs., say, Windows or Linux. You will also notice a massive improvement over the Nvidia cards if your workload is integer-heavy vs floating point, because of the massive number of "simple" stream processors in AMD cards vs the lower number of complicated compute cores in GeForce cards.

    Windows and Linux rely on the AMD/ATI drivers, which have some alignment optimizations that give about a 50% improvement in performance than the Apple-produced drivers.

    You'll also find that you'll need to be more careful writing your kernels in Mac OS X vs. Windows/Linux. They tend to segfault much more easily on the Mac.

    If you're looking to play with OpenCL the 5770 will do fine under OS X. You should be able to run most basic stuff. It's only when you start optimizing or going outside the basic operations that you may have problems.

    I ended up using my 3,1 and 5770 upgrade for validation runs and then built two linux machines with multiple AMD 69xx cards for brute force OpenCL results.

  • This card is very recent. OpenCL SHOULD be supported. I want this too, I hope someone can tell us for sure. But I think it IS supported as far as I have read.