Question : Memory Advanced ECC Mode with Mixed DIMM Capacities on Dell R710 PowerEdge

I've reviewed all doumentation for Dell PowerEdge R710 and chatted with Dell support and still can't find a definite answer to the question, can the server run in Advanced ECC Mode if I'm using both 1-GB and 2-GB UDIMMs.  The server has 2 CPUs, the amount of each type of DIMM and DIMM placement is identical for each CPU, I've tried different DIMM placements but whenever I add the 2GB DIMMs anywhere Advanced ECC mode alway becomes disabled.

Answer : Memory Advanced ECC Mode with Mixed DIMM Capacities on Dell R710 PowerEdge

The memory you are using must be x4 or x8 based DIMMS for Advanced ECC

Optimized - uses all the memory channels to use all the memory and will produce the best performance

Advanced ECC- will pair up memory channels on each processor and are required to be in specific slots on the MB (I think the slots with the white tabs)  I think you will need two more 2GB (one for each processor) to get Advanced ECC to work.