When a DIMM fails, the DIMM pair is disabled, and because of the system DIMM architecture, other DIMMs are disabled as well.
The Oracle ILOM PRSNT command reports these inaccurately. For example, 32 GB of DIMMs might be disabled, but only 16 GB are reported as disabled. Also, the faulted pair might be listed as Present.
For example, if D9 or D13 is faulty, in the Oracle ILOM System Monitoring > Sensor Readings tab, you might see:
/SYS/BL0/P0/D0/PRSNT Entity Presence Present but disabled /SYS/BL0/P0/D1/PRSNT Entity Presence Present but disabled /SYS/BL0/P0/D4/PRSNT Entity Presence Present but disabled /SYS/BL0/P0/D5/PRSNT Entity Presence Present but disabled /SYS/BL0/P0/D8/PRSNT Entity Presence Present /SYS/BL0/P0/D9/PRSNT Entity Presence Present /SYS/BL0/P0/D12/PRSNT Entity Presence Present /SYS/BL0/P0/D13/PRSNT Entity Presence Present