Haswell is the big news of Computex this year and for the next year it will be the big push in all of the marketing that will be seen around the world of PCs. Intel has put more focus than ever on the graphics capabilities of Haswell even going so far as to increase the size of the CPU die to accommodate the large on-board graphics that it offers. The question remains, has Haswell killed the GPU?
Intel has up to 5 levels of graphics coming out with the Haswell platform, 2 of which contain the Iris nomenclature (Intel Iris 5100 and Iris Pro 5200 graphics). For now the sake of this article I will focus on the so called GT3 level Iris Pro 5200 graphics found on 47W chips at the top of the Haswell mobile family because this is where Iris is designed to kick the competition hardest. Iris Pro contains 128MB of RAM which is not only available to be used for graphics, but can also be used as an ‘overflow’ cache for the CPU, making Iris Pro chips some of the deadliest chips for computing in the mobile space when not even considering their graphics prowess. How did Intel get to 128MB? At current workloads, Intel didn’t see much benefit beyond 32MB of RAM however it wanted the design of the chip to be future proof. So Intel doubled the size of the RAM to deal with any increases in game complexity, and then doubled it again just to be sure.
At 47W for the total solution, Intel is banking on the fact that although it is slightly more expensive to purchase than a standard, non Iris toting Haswell CPU + nVidia discrete mobile GPU, Iris will give OEMs (PC makers) the ability to lower the power requirements of a system dramatically. A discrete nVidia GPU (like the GT 650M used in the 15-inch Retina MacBook Pro) uses 45W of power on its own and in many cases offers only a slight performance bonus over that of Iris Pro. Power of course is not the only factor to consider, with less energy being used by dropping the GPU, less heat will be generated, less heat means less fans which in turn means even more power saving. Haswell already boasts the largest power saving from a new generation of Intel CPUs ever, considering that many notebooks could do away with additional cooling and GPU requirements, battery life could improve on a notebook to such a drastic extend that all day use would be an easy task.
Back to the question at hand: “Has Haswell killed the GPU?”.
In saying that though, Intel has just created the opportunity to seize a large portion of the market simply by removing the need for the extra components, space, heat and power requirements that a GPU brings. I could easily live with a laptop that doesn’t offer a discrete GPU as many people already do with Ultrabooks and any MacBook Pro under 15-inches in size and for that reason I think that we have just seen the single biggest move in mobile computing in since the MacBook Air made solid state storage ‘normal’.
If you require a deeper dive into the new Iris Pro level graphics, then I would highly recommend that you read the review by AnandTech.