RDRAM is dual channel, so each channel must have similar RIMMS.
here is what Intel says:
A, B, C and D are markings on the motherboard.
[maroon]RIMM A = RIMM-2 (Channel A)
RIMM B = RIMM-1 (Channel A)
RIMM C = RIMM-4 (Channel B)
RIMM D = RIMM-3 (Channel B)
RIMMs must be installed in pairs, and the memory configuration of each channel MUST match. Thus, RIMM-1 and RIMM-3 must be the same size, density, type and speed. RIMM-2 and RIMM-4 must also be the same size, density, type and speed. Using the encoded part numbers on the RIMMs is the best way to determine if the parts are the same.
When using only two RIMMs, you must install a Continuity Rambus Inline Memory Module (CRIMM) in those slots that do not contain RIMMs. In order to optimize memory performance, you must first populate RIMM-1 and RIMM-3.[/maroon]
you will find the channel details in the manuals of respective motherboards.
girish
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