For those trying to skimp on a system memory purchase for a new AMD Kaveri system or just curious about the impact the system memory bandwidth has on the latest-generation APUs, here are some benchmarks looking at the overall system memory performance when testing all major DDR3 system memory speeds between DDR3-800MHz and DDR3-2133MHz.
Going back two years was the last time I looked at the AMD memory performance when back then it impacted the Trinity APUs. The faster the memory, the better the overall system performance: with AMD's Kaveri this continues to hold true, if not more true, with the system craving all available memory bandwidth especially for the graphics tests with the more powerful Radeon R7.
From the ASUS A88X-PRO motherboard that was sent over as part of the Kaveri review system by AMD, the memory speeds of DDR3-800MHz, DDR3-1066MHz, DDR3-1333MHz, DDR3-1600MHz, DDR3-1866MHz, and DDR3-2133MHz was tested. The timings on the system memory were maintained the same at all frequencies so it's solely a comparison of the memory bandwidth as it impacts the A10-7850K Kaveri APU at its stock frequencies. DDR3-2400MHz frequencies are also attainable on this system, but the memory supplied by AMD was only rated for DDR3-2133MHz and in an overclocked mode it could not obtain DDR3-2400MHz frequencies. However, in the coming days on Phoronix will be some tests from Kaveri with DDR3-2400MHz memory.
The system memory used during testing was branded the AMD Radeon Memory Gamer Series, manufactured by Dataram Corporation, and rated for DDR3-2133MHz at 1.65 Volts with 10-11-11-30 timings. A wide range of both processor and graphics tests was done from the Ubuntu 13.10 64-bit Linux installation with the 3.12 kernel and latest Catalyst graphics driver. All of the benchmarking at the six memory frequencies was handled via the Phoronix Test Suite.