General Memory Information - IBM 265 Service Manual

General Memory Information

Be sure to unplug the power cables before removing or installing the memory DIMMs to
avoid damage to them.
Memory DIMMs must be installed in matched (size and speed) pairs. Refer to "Memory
Card and Memory DIMMs" on page 256 for labeling of the memory card and
instructions on DIMM removal and installation. (Do not, however, replace the covers as
directed while troubleshooting this problem.) A single memory DIMM pair may be
installed in module slots J1 and J2 (not slots J1 and J3). A second memory DIMM pair
could be installed in module slots J5 and J6 (slots J3 and J4 do not have to be
populated first). Along these same lines, there is no requirement that memory DIMM
slots J1 and J2 be populated before another slot pair.
Step 1240-1
1. Turn off the power.
2. Remove all installed memory DIMMs from the memory card. Record the positions of
the memory DIMMs so that when instructed to reinstall them they can be installed in
their original positions.
3. Install one pair of memory DIMMs.
4. Turn on the power.
Does the system stop with a memory checkpoint or memory error code displayed
on the operator panel?
NO
YES
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Service Guide
If there are no more memory DIMMs to be installed, reseating the DIMMs on
the memory card has corrected the problem.
If there was more than one pair of memory DIMMs on the memory card, go to
"Step 1240-2" on page 47.
Go to "Step 1240-3" on page 47.