Although we haven’t even seen the first generation of Mali T600 series GPUs shipping, ARM is already announcing the second generation of T600 GPUs, not only for the Mali T604, but also for the GPU-compute-oriented Mali T658. These second generation GPUs are the Mali T624 (4 cores) and Mali T628 (8 cores) for the graphics-oriented chips, and Mali T678 for the GPU compute oriented product.
Why is ARM announcing such a confusing move right now? Because it seems that, while they think GPU compute will be an important part of mobile GPUs in the future, they aren’t sure just how important it will be. GPU compute hasn’t really caught on in the mainstream PC market. ARM’s CPU and GPU architecture will offer some improvements in efficiency thanks to the “cache coherency” (which ARM will start using in SoCs equipped with both Cortex A15 CPUs and Mali T600 GPUs). But chances are GPU compute will not catch on in the mobile space either.
This is why ARM’s GPUs will take two paths. The first one, which includes the Mali T601, Mali T604, Mali T624 and Mali T628 designs, will continue to be fully graphics-oriented. The second one, with the Mali T658 and Mali T678, will focus a little more on GPU compute (Mali T658 will be offering four times the GPU compute performance of Mali T604, for example). It also seems that the highest-end smartphones and tablets will use the GPU compute oriented designs, which support 4k and even 8k resolutions, while the graphics-oriented GPUs will be available in the lower-end devices.
ARM has also announced a way for developers to solve the “fragmentation of standards” problem when it comes to using different texture codecs between different mobile GPUs. The solution is called Adaptive Scalable Texture Compression (ASTC), occupies only 2% of the chip, and includes all existing textures, color standards, and bit-rates, so developers will only have to support ASTC, and their game will work nicely on any mobile GPU out there.
The Mali T604, Mali T658, and even the Mali 450 chips for mid-range smartphones are expected to arrive by the end of the year (let’s hope in one Nexus device, at least), while the next-gen Mali 624, Mali 628, and Mali 678 are supposed to arrive next year.