System Memory; Supported Memory Module Configuration - Dell PowerEdge C6220 Hardware Owner's Manual

System Memory

Each system board has sixteen DDR3 memory module slots for the
installation of up to sixteen unbuffered or registered DDR3-1333MHz
(1600MHz @2 memory modules per channel) memory modules to support
processor 1 and processor 2. See "System Board Connectors" on page 255
for the location of the memory modules.

Supported Memory Module Configuration

For the sequence of the sixteen memory-module slots, see Figure 3-47. The
system requires at least one memory module installed on processor 1's
DIMM slot 1 in order to be booted up. When you insert the memory
module(s), always start with CHA_A1. The optimized memory module
installation sequence is 1/2/3/4/5/6/7/8.
See Table 3-2 and Table 3-3 for possible memory configurations.
Figure 3-47. DIMM Slot Locations
1 DIMM_A3
3 DIMM_A4
5 DIMM_B1
7 DIMM_B2
9 DIMM_B3
2 DIMM_A7
4 DIMM_A8
6 DIMM_B5
8 DIMM_B6
10 DIMM_B7
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