Imagination, the company that makes the PowerVR GPU's that usually go in Apple's iOS devices, has confirmed that Samsung is using their PowerVR SGX544MP3 GPU in the upcoming Exynos 5 Octa SoC, and in their Galaxy S4 device, which is about to get announced today.
The move seems to be a loss for ARM's own GPU, Mali, which has been used in Samsung's devices for the past couple of generations, after Samsung used the PowerVR SGX540 in the original Galaxy S. The last time Samsung used a Mali GPU was in Exynos 5 Dual, which was found in the Nexus 10 and the ARM Chromebook. But why did Samsung make this move?
The reason probably has to do with raw performance. Apple's devices, while usually losing in CPU performance (if the browsers being used to test the performance would be equal), have kept winning in GPU performance by a large margin in the past few years. Part of it is because of Imagination's more powerful GPU, and part is because they've been willing to use at least twice as big GPU's in their SoC's, compared to everyone else.
This is what puzzles me most about this move. I have no doubt the Galaxy S4's GPU will be at least twice as fast as the iPhone 5, because it will be clocked twice as high. The question is if it will be as fast as the next iPhone, and I'm pretty sure it will be no match for Apple's A7X GPU found in the next iPad, because Apple will use a GPU that is twice as large as the one in the next iPhone and in the A7 chip. So for Samsung's sake, I hope they at least intend to use a 6 core PowerVR SGX544, or something similar, for their upcoming tablets, if they really want to be competitive.
But they will still be behind in one area compared to Apple. Apple will be using the brand new OpenGL ES 3.0-enabled GPU architecture: PowerVR Series 6. Samsung will not. If they made such a huge change to PowerVR, and they went through all the trouble of writing new drivers, why didn't they just go with Series 6, for which they'll probably need new drivers anyway if they plan on using it next year. Using PowerVR SGX544 makes Samsung no closer in matching Apple's GPU's this year, although they should get a bit of positive PR for a couple of months until whenever Apple decides to launch its next iPad or iPhone.
The GPU will still be unmatched by anything, except perhaps Tegra 4's GPU, in the coming months, and it should also be significantly faster than the Adreno 320 they are going to use in US, considering Samsung will repeat the decision from last year to use Qualcomm's chips with integrated LTE in US.