The Xeon 1230V3 does not support quad channel. If you throw in 4 sticks they will still operate on dual channel. Where as if you want to have 2x16 instead of 4x8 that is motherboard dependent. Note that the Xeon 1230V3 does not support more than 32 GB, so even if you add more (lets say 2x16 and 2x8 or something), they wont be available.
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