No announcement yet.

Configure RAM speed for test?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Configure RAM speed for test?

    Hi, is it possible to configure the RAM speed for Memtest86? The default test uses 4800MHz which is the JEDEC#7 profile for my Corsair DDR5 RAM instead of the 5600MHz XMP profile set in the BIOS. After nearly five hours the test shows no errors at 4800MHz but I'd like to test at 5600MHz to be 100% sure as I'm in the process of debugging an intermittent boot error.

  • #2
    MemTest86 doesn't attempt to set the RAM speed nor timings.

    It just uses whatever values you have set in BIOS (or if you have set nothing, then whatever the default BIOS values are).


    • #3
      Thanks for the reply David. I've tested several times with RAM set at XMP-5600 in BIOS but frequency during the test is always 4800MHz. Memtest86 is doing its job correctly so can any conclusion be drawn from that which could indicate a faulty memory controller or faulty RAM? The system is stable once booted.

      I've tested with a BIOS embedded version of Memtest86 and made a short video to show selected speed and transition to start of test.


      • #4
        Again, MemTest86 doesn't set the speed.
        The speed it reports is the hard coded SPD data from the RAM sticks. This is normally what the BIOS would be using (except there are often multiple profiles to pick from). But in an overclocking situation you won't be using the recommended SPD values. So MemTest86 won't display the speed being used in this case.

        Update June 2023: From release V10.5 the current RAM clock speed in Megatransfers/Sec (MT/Sec) is displayed for some CPU models. At the moment this list is the following CPUs: AMD Ryzen Zen 1/2/3/4, Intel Skylake, Kaby Lake, Alder Lake & Raptor Lake. We expect to add additional CPUs in the future. We also display the current timings in use, the voltage level and if the RAM is running in dual channel mode.​


        • #5
          I'm running memtest v10.5 on a Ryzen 9 7900X with RAM set to DDR5-6000 in the BIOS. During tests, memtest reports speed of 3734 MT/s x2 Channel. Is that as expected?


          • #6
            As far as we know it is reporting the correct data.

            Can you post the MemTest86 debug log

            A screen shot / photo from BIOS showing the speed might also help for comparison.

            It might be that you are looking at the RAM's capability in BIOS and not the current speed in use.

            According to AMD's web site these are the max RAM speeds possible for that CPU.
            2x1R, DDR5-5200
            2x2R, DDR5-5200
            4x1R, DDR5-3600
            4x2R, DDR5-3600

            So with 4 sticks of dual rank RAM only 3600MT/sec is possible.


            • #7
              The BIOS has enabled an EXPO profile to bring the RAM to DDR5-6000 (photo attached). With Windows running, CPU-Z shows the DRAM frequency as approximately 3000 MHz (screenshot). The memtest log is attached as well. Thanks for your help! Click image for larger version

Name:	CPU-Z.png
Views:	866
Size:	40.5 KB
ID:	55324 Click image for larger version

Name:	BIOS.jpg
Views:	884
Size:	461.8 KB
ID:	55326 MemTest86-20230621-111733.log


              • #8
                Thanks for the logs.

                We made some fixes to the memory speed detection for this chipset. Can you give this debug build a try:


                • #9
                  Originally posted by keith View Post
                  Thanks for the logs.

                  We made some fixes to the memory speed detection for this chipset. Can you give this build a try:
                  Hm, for some reason this one won't boot for me (complains that the hardware configuration has changed and asks for recovery key, then just boots to Windows). My hardware & my BIOS settings haven't changed; in particular, the BIOS is still set to UEFI booting, compatibility mode disabled.


                  • #10
                    Debug build will not have been signed by Microsoft. So secure boot won't work. It takes about a week to get Microsoft to sign a UEFI program.


                    • #11
                      Originally posted by keith View Post
                      Thanks for the logs.

                      We made some fixes to the memory speed detection for this chipset. Can you give this debug build a try:
                      I experienced the same issue.
                      MemTest86 v10.5 build 1000 reports the speed of my DDR5-6000 as 3734 MT/s.​
                      I tried the debug build 1003, and the speed is shown correctly now.

                      Is the issue only a display bug? Or does it affect the ram speed during the test?
                      Should I re-run the test if I had already run it on build 1000?


                      • #12
                        MemTest86 never sets the RAM speed. It only reports on the speed set in BIOS and in the SPD configuration chip. So it is only a display issue.
                        Of course it would be nice to have the display as correct as possible.