: News
: Reviews
: Editorials

: Archives
: About
: Contact
: Advertising
: Privacy
: Links
: Forums




Changing the Computing Landscape Forever


Why GP-GPU May Hurt Intel


by Josh Walrath


            I realize the sub-title of this article may be a bit extreme, but we are on the cusp of a change in computing that many people may not realize is here.  It is only now that we are seeing larger announcements and greater talk about General Purpose GPUs and how it will affect the future of not only the desktop applications, but of high performance computing itself.  While we may be a generation away from seeing products that will fulfill the promise of GP-GPU, the groundwork is being done by many competitors to take advantage of this exciting new world. 

What is GP-GPU

            The modern DX9 based GPU is a floating point monster that can be used as a powerful stream processor.  For example, the X1900 (R580) features 48 pixel shader pipelines that can handle 32 bit operations.  Now, this is not IEEE 32 compliant, but it is still 32 bit.  By utilizing specific programming, this floating point potential can be tapped and utilized when properly applied.  This does not mean that Windows can be run on a GPU, as it is most definitely not X86 based!  A current GPU can be viewed as a very strong tool in specific instances.  For better or for worse, the primary functionality of a GPU is still graphics processing, and the architecture is designed to do just that from the very beginning.

            Most of the GP-GPU software people are of the opinion that ATI hardware is faster than NVIDIA hardware when it comes to GP-GPU, and I am not one to deny that.  When looking down from 10,000 feet we see that overall shader performance does favor ATI, and their branching unit (which can be very, very handy in GP-GPU applications) is more advanced than what NVIDIA offers in the 7x00 series.  Add onto that the programmable memory controller and Ringbus architecture, we can see that in such a general purpose setting the ATI hardware is the better candidate.  This does not mean the hardware is perfect though.

            Both ATI and NVIDIA know of the potential of GP-GPU, and over the past few years both companies have brought in people to help achieve higher performance and greater compatibility with their hardware for GP-GPU purposes.  ATI may be ahead in the game right now, but the truth is both companies are working very hard to include greater GP functionality in their upcoming products.  Both R600 and G80 should have a much greater amount of performance and functionality over previous architectures.

            So if the stakes are so high, why are we really only hearing about GP-GPU right now?  There appear to be several reasons.  It wasnít until DX9 GPUs hit the market that people started to think of these products as floating point machines.  ATIís first generation could only do FP24, which is not terribly useful for most scientific applications.  NVIDIAís FX series had FP32, but performance was not great when utilizing it and the overall architecture was too constrained for general purpose use.  When the GeForce 6 series came out, it gave enough features and performance for work to really start in GP-GPU, plus the addition of branching (which is a key feature for general purpose programming).  ATIís X1xx series was later released, and with its advanced memory management and branching performance, programmers had a lot more flexibility (and a lot more interest) to develop software that will take advantage of such hardware.  It also helped that the installed base of computers with SM 3.0 functionality finally became significant.

            The software and hardware have finally become mature enough for this functionality to be exposed.  The announced applications are only scratching the surface when it comes to potential for GP-GPU, and this will have a tremendous impact on all future High Performance Computing applications, not to mention what will trickle down to the desktop.


Next:  Why AMD bought ATI


If you have found this article interesting or a great help, please donate to this site.


Copyright 1999-2006 PenStar Systems, LLC.