Performance Dependence on the Memory Frequency
When we tested the Radeon HD 7660D graphics core performance in games, we suspected that it sometimes lacked memory bandwidth. It is quite easy to check, since the Trinity memory controller works perfectly fine with high-speed DDR3 SDRAM. So we decided to compare the performance of the AMD A10-5800K based system with different memory types from DDR3-1333 to DDR3-2400. Note that when you select DDR3-2133 or higher memory mode, Trinity memory controller requires Command rate to be set to 2T. Nevertheless, the system remained totally stable. As a result, we used the following memory timings for different test modes:
- DDR3-1333 9-9-9-27-1T;
- DDR3-1600 9-9-9-27-1T;
- DDR3-1866 9-11-9-27-1T;
- DDR3-2133 11-11-11-33-2T;
- DDR3-2400 11-11-11-33-2T.
And here are the obtained results:
Graphics core performance proved amazingly scalable as the memory frequency and bandwidth increased. By simply raising the memory frequency by 266 MHz, we could boost the fps rate by 10-15%. Of course, as the memory frequency increased, this dependence becomes less prominent, but nevertheless, if you are building a Trinity based system and intend to use its graphics core for 3D applications, you must pay special attention to finding high-speed DDR3 SDRAM. This is excellent new for overclocker memory makers, because it creates potentially larger market for them. It is a very convincing argument that you can easily boost the gaming performance of your AMD A10-5800K processor by as much as 15-20% by simply replacing the common DDR3-1600 with DDR3-2400 in your Socket FM2 system.