It is not necessary to populate the DIMM slots with identical memory because if non identical memory is detected, memory interleaving will automatically be disabled.
At post bootup, the server will identify whether interleaving is enabled or disabled depending on the memory configuration. This is not an error message, this is an advisory message, the server should not fail POST. Further information can be gained from the RBSU main menu on the memory configuration.
Whilst it is not advised to mix memory of different types (eg PC2100 & PC2700), my experience has always been that the server will either error and not work with the higher memory in, or the memory will step down to the lower speed (I have seen this with the ML530 G1 & G2).
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"Who is General Failure and what is he doing on my computer?"
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