DDR and Rambus RAM both must be matched pair?

arayzm · July 2006

I found DDR ram is not the answer in the demo questions from the comptia website execpt the rambus ram is the only answer.
second question: I only have to choose one if the question have not say this question is multiple .

OpenSource · July 2006

arayzm wrote:

I found DDR ram is not the answer in the demo questions from the comptia website execpt the rambus ram is the only answer.
second question: I only have to choose one if the question have not say this question is multiple .

Uh, what question??? Post the question and we'll give you an answer.

- Joey

TheShadow · July 2006

RAMBus needs either a matched pair or a single stick and a special terminator stick called a continuity card. You can spot it right away because the RIMM stick will have a non-removable full length heatsink and you will have this funny little board in the next slot. Inexperienced tech seem to like to remove it and fail to put it back or in the wrong place until they ponder why memory does not work.

DDR can be used in singles unless you want to use the dual channel logic of your motherboard. Was that what you were looking for?

edit - to answer how many do you check? If the answers have round places then only one answer is possible. If they have squares then two or more answers are required and CompTIA tests normally tell you how many you must check.

OpenSource · July 2006

TheShadow wrote:

RAMBus needs either a matched pair or a single stick and a special terminator stick called a continuity card. You can spot it right away because the RIMM stick will have a non-removable full length heatsink and you will have this funny little board in the next slot. Inexperienced tech seem to like to remove it and fail to put it back or in the wrong place until they ponder why memory does not work.

DDR can be used in singles unless you want to use the dual channel logic of your motherboard. Was that what you were looking for?

edit - to answer how many do you check? If the answers have round places then only one answer is possible. If they have squares then two or more answers are required and CompTIA tests normally tell you how many you must check.

Actually, RAMBUS did away with the "continuity module" in the later revisions of RAMBUS memory (RDRAM), right before they basically stopped its development. But with the earlier versions, yes, you need to use something referred to as a "continuity module" or "terminator module", though "continuity" is actually the correct term.

In addition, exactly like DDR-SDRAM, if you want your RAMBUS compatible motherboard to act in dual-channel mode, you will need two "matched" modules of the same RAM. Note though, out of the dozens of PC"s I've built, only one actually used RDRAM. In fact, RAMBUS basically put themselves out of business and DDR-SDRAM has more then picked up the slack.

- Joey

TheShadow · July 2006

However has anyone ever seen a motherboard that supported the newer revisions. I thought they were mostly for playstations. Intel had dropped RIMMs like a hot potato by then also being the primary chipset maker.

OpenSource · July 2006

TheShadow wrote:

However has anyone ever seen a motherboard that supported the newer revisions. I thought they were mostly for playstations. Intel had dropped RIMMs like a hot potato by then also being the primary chipset maker.

I've only worked with RDRAM once and I have not seen an RDRAM motherboard for quite some time (maybe years). But from my understanding, the original RDRAM was RIMM-16 (16-Bit), which required "matched pairs" and "continuity modules", however, the later revision of RDRAM was RIMM-32 (32-Bit), which no longer required either of the above.

RIMM-16:

PC600 (RIMM1200)
PC700 (RIMM1400)
PC800 (RIMM1600)
PC1066 (RIMM2100)
PC1200 (RIMM2400)

RIMM-32:

PC800 (RIMM3200)
PC1066 (RIMM4200)
PC1200 (RIMM4800)

- Joey

DDR and Rambus RAM both must be matched pair?

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