Rimm Installation Guidelines - Dell Precision 620 Upgrade Manual

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RIMM Installation Guidelines

You must install RIMMs in pairs. This means that the RIMM in each socket on one
MEC must be the same memory capacity, density, and speed as the corresponding
RIMM in the same socket on the other MEC. Also, for either channel A or B of each
MEC, if one socket contains a RIMM, then the other socket must contain either
another RIMM or a continuity RIMM (CRIMM).
As an example, if you install only one pair of RIMMs in the RIMM1_A socket of each
MEC, then you must install a CRIMM in socket RIMM2_A of each MEC. Channel B
(sockets RIMM3_B and RIMM4_B) may remain empty, or it may contain one or two
CRIMMs per MEC (see Figure 1).
However, if channel A contains two RIMMs and you want to install additional RIMMs,
the preceding rules also apply for channel B.
NOTES: If 512-MB RIMMs are used, they must be populated starting with the bottom
RIMM socket (RIMM4_B, the one closest to the system board) and working up. For
example, see the configuration in the last row in Table 1. In this example, you would
insert the 512-MB RIMMs into the bottom three sockets (RIMM4_B, RIMM3_B,
RIMM2_A) and insert a CRIMM into the topmost socket (RIMM1_A).
When you add 512-MB RIMMs from a customer kit, you must remove all existing
RIMMs and reinstall the new 512-MB RIMMs, beginning with socket RIMM4_B and
working up on each riser board in mirror fashion.
Dell does not recommend or support the mixing of old and new 512-MB RIMMs in
sockets RIMM1_A and RIMM2_A.
Table 1. Sample Factory-Installed RIMM Configurations (per MEC)
For Total
Desired
RIMM1_A (top)
Memory:
128 MB CRIMM
256 MB CRIMM
384 MB 128 MB
512 MB 128 MB
512 MB CRIMM
768 MB 256 MB
1024 MB 128 MB
1024 MB 256 MB
1536 MB 256 MB
2048 MB 256 MB
Populate both MECs as follows:
RIMM2_A RIMM3_B
64 MB Empty
128 MB Empty
64 MB CRIMM
128 MB CRIMM
256 MB Empty
128 MB CRIMM
128 MB 128 MB
256 MB CRIMM
256 MB 256 MB
256 MB 256 MB
System Memory Upgrade
RIMM4_B
(bottom)
Empty
Empty
Empty
Empty
Empty
Empty
128 MB
Empty
CRIMM
256 MB
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