8 Replies Latest reply on Sep 25, 2018 3:26 PM by mirh

    Memory Controller Details For All AMD CPU's?


      Having difficulty in finding details / specifications of integrated memory controllers within all AMD processors.


      For each and every AMD processor that has an integrated memory controller, I'm wanting information on -


      1) Maximum supported memory capacity

      2) Maximum supported memory frequency

      3) Supported memory chip data width(s) (ie x4, or x8, or x16)

      4) Supported memory chip densities (512Mb, 1Gb, 2Gb, etc.)

      5) And maximum memory controller voltage


      Already had a look at "Tech Docs" at AMD website, but haven't (as yet) found any documentation which answers all of the 5 listed parameters.


      Where can I find information on these 5 wanted memory controller parameters, please??


      Thank you.

        • Re: Memory Controller Details For All AMD CPU's?

          it is on Wikipedia Bulldozer (microarchitecture) - Wikipedia and you can Work from that link in right side to piledrive to newer cpus and older

            • Re: Memory Controller Details For All AMD CPU's?

              Thanks for the reply and the link.


              Perhaps I'm missing something there, but the only bit of information I found was the maximum supported memory frequency. Other parameters (maximum supported memory capacity (GB), supported memory data widths (x4, x8, x16), supported memory densities (512 Mb, 1 Gb, 2 Gb, . . ), and maximum memory controller voltage) were not found(?)


              I (tried to) follow several reference links also, but either the links are no longer valid, or the information at the links didn't seem to have the information I'm after.


              It seems this information I'm wanting is extremely difficult to find.


              AMD's CPU competitor has data sheets readily available which provides required (memory controller) information on their products. But it seems AMD is reluctant to provide (readily available) memory controller data (that I'm wanting)(?)


              Anyone have any further links to find the data I'm after, please?

            • Re: Memory Controller Details For All AMD CPU's?

              the other info you ned is on the Motherbords Companys homepage asus msi etc

                • Re: Memory Controller Details For All AMD CPU's?

                  Thanks for the comment, but I don't quite agree.


                  Motherboard manufacturers only quote maximum memory frequency and maximum memory capacity supported by their motherboards; there is usually no information on supported memory densities, supported memory data widths, nor maximum memory controller voltage. Also, the motherboard maximum supported memory frequencies and/or memory capacities might be limited by the number of memory slots and/or due to limitations in BIOS, regardless of the actual capabilities of the CPU memory controllers.


                  So, it is back to finding technical details (memory densities, memory data widths, and maximum memory controller voltage) of memory controllers within AMD CPU's. Is such documentation available??

                • Re: Memory Controller Details For All AMD CPU's?

                  Are there no AMD representatives participating in this forum who could answer this question?


                  Or do I have to contact AMD directly for information?

                    • Re: Memory Controller Details For All AMD CPU's?

                      Unless this information is available under Tech Docs, then it is private and confidential and we won't be making it public.

                        • Re: Memory Controller Details For All AMD CPU's?

                          If the information is not available in Tech Docs section (still haven't found information I'm after), then I fail to see why this information should not be readily available.


                          Confidential?, I would have thought not, since this information is important in finding compatible memory as well as knowing the limitations of the IMC in the event voltage adjustments have to be made to enable stable memory operation.


                          AMD's main CPU competitor makes the relevant technical details readily available. This makes finding compatible memory so much easier. Without the technical details at hand, then it would require trial and error to find compatible memory which would be time consuming and a costly procedure.


                          If AMD does NOT provide the required information, then they're shooting themselves in the foot, as this would tend to discourage people from using AMD based systems as compatible memory would not be readily and easily determined (apart from memory listed in tests).


                          The motherboard manufacturers and most memory module manufacturers usually provide a list of tested and compatible memory for the system of interest. But the tests are not comprehensive, there are still numerous other memory modules available which had/have not been tested. So in this case having the knowledge of supported memory configurations would help in selecting appropriate and compatible memory.

                      • Re: Memory Controller Details For All AMD CPU's?

                        It's not as comprehensively exposed as intel, but you can thankfully find all of that information in BKDGs nonetheless.

                        Look for "DRAM Controller", "DRAM Configuration" and "DRAM Address Mapping".

                        Be ready for every possible unholy combination (e.g. AM2 cpus can support unbuffered 2Rx4 modules, even though that's not in any spec whatsoever), and of course for anything before K8 you'll have to look at the chipset databook.


                        For Ryzen cpus it seems "PUB" is it, and you should check "Unified Memory Controller".