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While the need for higher graphics memory bandwidth continues to grow, it is evident that owing to the multitude of challenges in single ended signaling, pushing data rates beyond 6 Gbps is exceedingly difficult. To isolate, quantify and combat the most important factors that limit the performance of modern high speed single ended systems, a high speed GDDR5 memory system (link width: x32) has been designed using a Rambus prototype test-chip (TSMC 40 nm process node) and a leading single ended signaling graphics GDDR5 DRAM. Critical challenges faced in scaling the data rates up to 8 Gbps are presented and the varying impact of these challenges on the system margin is shown for increasing speeds. An example of a chip-to-chip system between two prototype test chips, that mitigates these performance limiting determinants, is shown to operate robustly at data rates beyond 8 Gbps. The ingredients of this system are likely techniques for the future graphics memories.