Ruifaria, Refer to the illustration below:  [IMAGE] There are guild lines to follow when populating memory on channels. The reason your server doesn’t boot when you put MEM DIMMs on A7, A8, A9 & B7, B8, B9 is due to the limitation imposed by Quad-Rank DIMM. Once the first slot in a channel, A1 or B1 is populated by Quad-Rank DIMM, then the second slot A4 or B4 should also be a Quad-Rank DIMM or other and the last slot A7 or B7 should be left vacant. As SysAdminTX said, “all memory channels (3 per processor with 3 dimm slots per channel on an R710) need to have the exact same memory dimm layout, unless the memory channel is left unpopulated (there do seems to be some exceptions to this though)” This means that the MEM DIMMs on slots A1, A4 & A7 have to be the same as DIMMs on A2, A5, A8 and A3, A6, A9. Similarly, DIMMS on B1, B4 & B7 have to be same as B2, B5, B8 and B3, B6, B9. Moreover, DIMMs A1, A4 & A7 = B1, B4 & B7 and so forth. You cannot get past 52 GB of memory because your memory channels are not balanced. The server will boot with massage,” memory configuration not optimal” You will need 4 additional Quad-Rank DIMMs for you to get optimal memory with the following matrix: A1, A2 & A3 and B1, B2 &B3 –16GB A4, A5 & A6 and B4, B5 &B6 – 2GB See link below pages 30 to 33 for more information: www.dell.com/.../server-poweredge-r710-tech-guidebook.pdf
I just bought a Dell Poweredge R710, it came with 18x 2GB DDR3 UDIMMs, so 36GB total memory. In an attememp to increase total memory, i've 2x addition 16GB DDR3 UDIMM QuadRank. I've just tried every combination I could, but could not get past 52 GB total, with BIOS warning of different geometry. What's the best I can do with 16x 2GB + 2x 16 GB DIMMs? Would an addition 16GB DIMM help?
PE R710 DIMM population