Rambus is a company, RDRAM is the RAM and it is what you might call QDR, if I am not mistaken. Much like the Pentium 4 processors bus clock, it triggers at a low voltage on the rising edge, a high voltage on the rising edge, a high voltage on the falling edge, and then a low voltage on the falling edge of the clock. This gives it 4 operations per actual clock cycle. Which means a 100Mhz. RDRAM part puts out the bandwidth of a 400Mhz. Regular SDR SDRAM part. Which means it can push some serious bandwidth without a needing a ridiculously high frequency clock. It is also why it matched so well with the Pentium 4 in Intels mind. However RAMBUS the company (which never actually builds anything) went screaming intellectual property on everyone and the cost of the memory went sky high. They backed down on a promise they made when attending a standards body meeting on SDRAM patents and tried to bully the memory makers so many refused to manufacture RDRAM.
Plus RDRAM has a very high latency because the memory chips weren't up to the task of feeding the bus so they are constantly behind the requests.
Last edited by jtshaw; 01-17-2004 at 08:40 PM.
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