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Nefarious wrote:

Alas, a big iron Mac is not in my near future.

And too bad the fabled midrange tower exists not. The 3870 is near half a TFLOP in compute power, the new $200 4850 fully 1 TFLOP. With a 3870 Mac & PC Ed. out now, one might guess there'll be a 4870 like it in 6 months or so. You do need a PCIe slot to put it in, tho, and an OS client of course.

I've a feeling the Mac client may have to wait on OpenCL, a year or so out, unless Stanford really gets on it. (They also need to update the Win client for the new 4xx0s).

Moving on, we have the other piece of Apple's new performance technology, the Open Computing Language (OpenCL). OpenCL is a C language for GPGPU computing, similar to CUDA and Brook+ for NVIDIA and AMD respectively. Currently CUDA and Brook+ are incompatible, both are C but the languages are different enough that programs are not portable between the two, and neither can compile for the other company's GPUs. Full GPGPU support has been notably absent from the Mac so far while CUDA and Brook+ have been supported on Windows and Linux for some time now. We have heard that Apple has wanted to add full GPGPU support to the Mac for some time now (having been one of the first companies to embrace early GPGPU usage for their video editing applications) but we have also heard that they are unhappy about the incompatibility between the GPGPU languages. They don't want to have to write two of everything, nor do they want their developers doing so. There are 3rd parties that offer GPGPU programming environments that are cross-GPU compatible, but these are expensive and not at all open in any sense of the word.

So we have OpenCL, Apple's proposed universal GPGPU programming language and API. From what we know it looks like Apple is trying to make OpenCL the GPGPU sibling of OpenGL, but like Grand Central Apple has said very little so far. We're not sure who (if anyone) else is backing OpenCL, although we expect AMD and NVIDIA to be on-board otherwise the whole effort will fall flat on its face without support from the GPU manufacturers. Apple has said it's beyond CUDA and Brook+, although we're not entirely sure in what way. From what we've seen of CUDA and Brook+, both are very powerful and very functional languages, so it's unlikely OpenCL is adding any new features that will expand what developers can do; nearly anything can already be done. Rather it seems Apple will be going the simplification route, as CUDA and Brook+ are anything but simple to program for; they may use C but they currently have many nuances that have to be dealt with. An even further generalized framework that's more open to less technical programmers may be what Apple is shooting for. But like Grand Central, we're going to be waiting some time until Apple fully explains where they're going and why.

http://www.anandtech.com/weblog/showpost.aspx?i=461