1. Double Data Rate Random Access Memory DDR-RAM, DDR-SDRAM ...Synchronous... RAM that transfers data on both 0-1 and 1-0 clock transitions, theoretically yielding twice the data transfer rate of normal RAM or SDRAM. DDR-RAM Article http://www.pcreview.co.uk/Article.php?aid=9. DDR-SDRAM Article http://www4.tomshardware.com/mainboard/00q4/001030/.