Double Data Rate 3 Synchronous Dynamic Random-Access Memory is a type of synchronous dynamic random-access memory (SDRAM) with a high-bandwidth interface, that was released in 2007. It is the higher-speed successor to DDR and DDR2 and predecessor to DDR4 synchronous dynamic random-access memory (SDRAM) chips. DDR3 SDRAM is neither forward nor backward compatible with any earlier type of random-access memory (RAM) because of different signaling voltages, timings, and other factors.