For RAM, you may want 8 * 8 GB, even if it looks a bit excessive at first. With 4 * 8, you will be running either one CPU Quad Channel or both in Dual Channel, missing the full Memory Bandwidth potential. Considering we're talking about LGA 2011 Xeons, you may want to use Buffered/ECC instead of Unbuffered/ECC. You will not have access to all the mainstream RAM variety, through.

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