13 Replies Latest reply on Jun 5, 2013 11:20 AM by LaciG

    6 x 4 or 3 x 8?

    LaciG

      I am increasing my RAM on an Intel Core I7 930 + ASUS P6X68D Premium configuration from 12 GB to 24 GB. My questions:

       

      1. This mother board accepts either 3 x 8 GB or 6 x 4 GB RAM configuration. Is there any advantage (speed, reliability, etc.) of either one?

      2. The mother board does not explicitly mention Error-Correcting Code (ECC). Do I have to chose memory without ECC?

      3. Any preferred memory for editing purposes (Crucial, Corsair, Kingston, Patriot, PNY, Mushkin, OCZ, G Skill, etc.)?

       

      Thank you very much,

       

      Laci.

        • 1. Re: 6 x 4 or 3 x 8?
          ECBowen Most Valuable Participant

          The 4GB sticks will have lower latency options but other than that the 3x 8GB would have better compatibility since only 3 sticks. You want unbuffered ram instead of ECC.

           

          Eric

          ADK

          • 2. Re: 6 x 4 or 3 x 8?
            Harm Millaard Level 7

            Laci,

             

            Choose memory without ECC.

             

            Most of these older 1366 platforms have difficulties with 8 GB sticks. Performance wise there is no difference between 6 x 4GB or 3 x 8GB.

            • 3. Re: 6 x 4 or 3 x 8?
              LaciG Level 1

              Hi Harm,

               

              Thanks for the reply. I will certainly not use ECC memories. However, it seems to me that the two answers (yours and Eric's) differ in the suggestion of the 4 GB vs. the 8 GB memories.

               

              Also, when I was asking about reliability, I was thinking of my two last years in the industry when I worked on (not flash but PCM: Phase Change Memory) reliability characterization. Without ECC if one cell goes wrong, then the whole memory unit has to be replaced. Seems to me that the 4 GB choice is better financially.

               

              Baased on your answer, I would chose 6 x 4 GB no ECC memories. Also, based on Eric's reply, I would use unbuffered RAM. My only question for him is what the "better compatibility" of the 8 GB sticks means.

               

              Thanks again,

               

              Laci.

              • 4. Re: 6 x 4 or 3 x 8?
                LaciG Level 1

                Eric,

                 

                Thanks for your help. As I mentioned in my reply to Harm, I am not sure I understand what the "better compatibility" of the 3 units vs. the 6 units mean. He specifically mentioned that my MOBO has problems with the 8 GB units - unless I misuderstood something.

                 

                Thanks again,

                 

                Laci.

                • 5. Re: 6 x 4 or 3 x 8?
                  Jim_Simon Level 9

                  I'd probably go with 3 x 8, if only because it leaves slots open for further expansion.

                  • 6. Re: 6 x 4 or 3 x 8?
                    LaciG Level 1

                    Thanks Jim. Well, the mother board specifications allow 24 GB maximum memory - I thought that this is a maximum, and I can't use more than this. Am I wrong? (BTW, what is the maximum determined by?)

                     

                    Thanks,

                     

                    Laci.

                    • 7. Re: 6 x 4 or 3 x 8?
                      Bill Gehrke Most Valuable Participant

                      Are you positive that that motherboard really supports 8 GB modules?  I do not have this motherboard but I just do not remember any motherboard of this series that could address  a 8 GB module.  The memory QVL sure does not show any.

                      • 8. Re: 6 x 4 or 3 x 8?
                        UlfLaursen Level 2

                        The QVL (Qualified Vendor List) on Asus's site only speaks of up to 4 GB modules and a max of 24 GB on 6 slots, so I am pretty certain it will only alowa up to 4 GB sticks.

                         

                        Ulf

                        1 person found this helpful
                        • 9. Re: 6 x 4 or 3 x 8?
                          Harm Millaard Level 7

                          Laci,

                           

                          Most of the specs of 1366 motherboards were written several years ago and I'm not sure they will be updated in time. When they were written 8 GB sticks were a rarity if they even existed at all. Hence that all 1366 motherboards specify 24 GB max and that is 6 x 4GB, not 48 GB, which would be 6 x 8GB.

                           

                          I just would not take the risk of trying out 8 GB sticks, but stick with 4 GB sticks. Even if it were possible to use 8 GB sticks, you would be hard pressed to notice any difference between 24 and 48 GB with a 4 core 930.

                          • 10. Re: 6 x 4 or 3 x 8?
                            JEShort01 Level 4

                            Definitely go with 6x4GB; I'd suggest 1600 speed sticks by G Skill other other vendor that certifies the exact RAM you choose for your exact motherboard for compatibility reasons

                             

                            Regards,

                             

                            Jim

                            1 person found this helpful
                            • 11. Re: 6 x 4 or 3 x 8?
                              Jim_Simon Level 9

                              Even if it were possible to use 8 GB sticks, you would be hard pressed to notice any difference between 24 and 48 GB with a 4 core 930.

                               

                              Maybe not in performance, but my thinking is that extra RAM comes in handy for RAM previews.

                              1 person found this helpful
                              • 12. Re: 6 x 4 or 3 x 8?
                                ECBowen Most Valuable Participant

                                The reason I mentioned better compatibility is due to 3 sticks instead of 6. Its far easier for the memory controller in the CPU to synchronize to 3 modules versus 6 over the bus. As far as I know the I7 Gen 1 chips should handle 8GB sticks. Only the board bios would effect this capability. If the board wont read those density modules and set the timings up right then it would not work. If it does then the CPU will.


                                Eric

                                ADK

                                1 person found this helpful
                                • 13. Re: 6 x 4 or 3 x 8?
                                  LaciG Level 1

                                  Harm,

                                   

                                  Actually I was curious about the difference between the 3 x 8 GB and the 6 x 4 GB configurations (both are 24 GB that is defined as the maximum RAM in the mother board manual). I will take your (and Bill and Ulf's) advice for the 6 x 4 GB configuration. Apart from some fine details mentioned by Eric (compatibility and latency for example that is a bit over my head) for me this arrangement seems to be the best and easiest to implement.

                                   

                                  Thank you and for all commenters (I learned a lot about RAMs),

                                   

                                  Laci.