Smartphones and tablets are becoming more and more powerful, replacing desktops and laptops as the users' main computing system. As these systems support higher and higher resolutions with more complex 3D graphics, a high-throughput and low-power memory system is essential for the mobile GPU. In this article, we propose to improve throughput/watt in a mobile GPU memory system by using intelligent scheduling to reduce power and multi-band radio frequency interconnect (MRF-I) to offset any throughput degradation caused by our intelligent scheduling. Overall, we are able to improve throughput 17% up to 66% while increasing throughput per watt by an average of 18% up to 26%.

The demand for capacity and off-chip bandwidth to DRAM will continue to grow as we integrate more cores onto a die. However, as the data rate of DRAM has increased, the number of DIMMs supported on a multi-drop bus has decreased. Therefore, traditional memory systems are not sufficient to meet both these demands. We propose the DIMM tree architecture for better scalability by connecting the DIMMs as a tree. The DIMM tree architecture is able to grow the number of DIMMs exponentially with each level of latency in the tree. We also propose application of Multiband Radio Frequency Interconnect (MRF-I) to the DIMM tree architecture for even greater scalability and higher throughput. The DIMM tree architecture without MRF-I was able to scale up to 64 DIMMs with only an 8% degradation in throughput over an ideal system. The DIMM tree architecture with MRF-I was able to increase throughput by 68% (up to 200%) on a 64-DIMM system over a 4-DIMM system.