IBM i 830 Repair Manual page 729

Figure 31. CCIN 2881 with pluggable DIMM
v DIMMs must be installed in groups of eight (octals).
v DIMMs are installed in the following order:
– A-B-C-D-E-F-G-H
– J-K-L-M-N-P-Q-R
– S-T-U-V-W-X-Y-Z
– 1-2-3-4-5-6-7-8
Locations and Addresses
Chapter 5. Locations, Addresses, and Part Listings
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