StorageJohn,  In order to maximize the amount of memory used I would suggest putting the 6 16GB dimms in slots A1, A2, A3, A4, A5 and A6. After that then place an 8GB dimm in slot A7, A8, and A9. This is to maintain the requirements of the memory channels. Seen below. [IMAGE] Let me know if this helps.
Hello team, we have R710 with single cpu with populated 9 dims with 8gb memory. We now have 6 x 16 gb memory in order to upgrade memory, what is best procedure to intermix memory to populate 3 more slots with 8 gb memory?  Is this even doable?
Dell R710 single CPU