Direct Rambus DRAM 或称 DRDRAM（有时也称Rambus DRAM 或 RDRAM）是Rambus公司设计制造的一种同步DRAM。

最初支持RDRAM的电脑主板是在1999年登场。这些产品与PC-800 RDRAM兼容，以400MHz频率工作并具有1600MB/s的传输速度，使用184针的RIMM插座。

数据在时脉信号的上升(Positive Edge Trigger，PET)与下降(Negative Edge Trigger，NET)皆传输数据(双向数据)。由于销售需要，命名方面为时钟频率的二倍(避免与 DDR 内存命名方式重复)，400MHz规格的Rumbus被命名为PC800，使用64bit的168针DIMM插座并提供1066MB/s的传输速度。这比以前的 PC-133 SDRAM速度大幅提高(PC-133工作于133MHz)。

Rambus DRAM (RDRAM'), and its successors Concurrent Rambus DRAM (CRDRAM) and Direct Rambus DRAM (DRDRAM), are types of synchronous dynamic RAM developed by Rambus from the late-1980s through to the early-2000s. The third-generation of Rambus DRAM, DRDRAM was replaced by XDR DRAM. Rambus DRAM was developed for high-bandwidth applications, and was positioned by Rambus as replacement for various types of contemporary memories, such as SDRAM.