Sam Naffziger, an AMD Fellow, gave a keynote on CPU-GPU integration recently. In this blog-post, I will summarize Sam's excellent talk and explain why this technology could change our industry.
3D Integration a long-term solution: In the long term, Sam feels 3D integration could be a promising solution. He discussed how one could stack DRAM, the GPU, the CPU and IOs/analog on separate layers of the stack. This helps tackle memory bandwidth issues which are key for APUs. Furthermore, GPUs and CPUs need their own optimized interconnect stacks and device libraries, and so 3D stacking GPUs and CPUs might be useful, especially for mobile applications that are less constrained by heat. However, Sam feels there are many challenges with manufacturing 3D stacks right now. Please see Fig. 8 for more details.