DDR Memory

DDR, the short form of Double Data Rate is one kind of memory module that transfers data at a doubling rate than a SDRAM memory module. It means it transfers two data portion per clock sequence. In order to get the maximum performance, this memory needs to be used in a moderately updated computer system.

However, if a memory module is labeled with DDR-800, then it is capable of working at 400MHz speed. The label indicates the maximum range that this memory module can support. Since, the controller used for this kind of memory is located outside the module and somewhere within the CPU, so the data transfer rate may vary accordingly.