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[SOLVED] 2 rams with different speeds running at different speeds

Jun 17, 2022
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Hi,
I have always thought that different frequency rams would always run at the lowest ram's frequency i.e. having a D3600 and D3200, all ram would run at 3200.

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My CPU-Z pictures above seem to contradict this idea. See columns XMP-3200 and XMP 3596 (1600MHz is for 3200, and 1798 MHz is for 3596). Why is this the case? Is there something I am not seeing here? Also, I have heard that possibly removing my lower speed ram sticks would speed up my build... is this true even if my CPU-Z pictures are telling the truth?

Thank you,
Oronto
 
Solution
Your ram is running at 3600mhz (effective).
Actual frequency is 1800mhz. But 2 data transfers per clock give 3600mhz effective frequency.
That's how DDR technology works.

I'd suggest you set Command Rate to 2T.
Running 4 modules with 1T command rate may introduce ram errors.
Yes, it IS running at that speed, but it should NOT be possible unless it's been manually configured to run that way as two of those DIMMs have XMP profiles that are 3200mhz, so something is definitely unusual here.

I'd recommend running Memtest86 to verify that the configuration is stable and if it is, well, why look a gift horse in the mouth I guess. You can change the command rate in the advanced settings section of the memory settings in the BIOS. You...
Those are JEDEC profiles, not the speeds your RAM is running at. To see what speed your memory is ACTUALLY running at, you need to look at the Memory tab.

But, we HAVE seen memory being misreported as running at different speeds before, but it is always due to physical problems with the motherboard that cause this to happen. Memory cannot run at different speeds on the same board. It is not even possible due to the nature of the memory controller.

As to whether it is more beneficial to run two DIMMs at the faster speed, or the full capacity at the slower speed, only you can answer that based on WHAT you are actually doing with the machine and whether you are actually seeing any benefit from having 32GB rather than 16GB. If you are not using more than 16GB at any time, then running less memory faster is technically your better option. If you are using more than 16GB, then running all four at the slower speed is preferable.
 
Hello again,
Thank you for the insight into the removal of my memory slower memory.
This is a picture of my memory tab. It seems to claim (all? ) my dram is running at 1800 Mhz, but I am skeptical. Would this be a case of misreporting?
KGUrIdu.png

Thanks again,
Oronto
 
What does it show in your BIOS? If you manually set the memory speed to 3600mhz in the BIOS, then it is probably all running at that speed and it is likely that you have an unstable memory configuration at the moment. If you did not manually set the memory speed to 3600mhz in the BIOS and only enabled XMP, and all four DIMMs are running at 3600mhz, then there is a problem with your motherboard OR somehow (Generally user required to enable this) some form of memory overclocking has been enabled if your board supports that.

Download HWinfo, install it, run it, choose the "Sensors only" option and uncheck the "Summary" option, and then scroll down to the memory section to see what IT is showing as far as the memory speed.

You can also, for an additional opinion, download the free version of Thaiphoon burner, and see what that is saying as well.

It would be helpful to know your FULL hardware specifications.
 
Hi Darkbreeze,
I do have XMP enabled, but I do not believe I know how to manually set memory speeds to 3600mhz, so that shouldn't be it. The motherboard is a msi tomahawk b450 (NOT MAX) (MS-7C02). My gpu is NVIDIA GEFORCE RTX 3080 TI. My CPU is AMD RYZEN 5 3600X. Is this sufficient?
Is this the memory section you were speaking of?
h6VaUBM.png

It seems to say the same thing.

Thanks again,
Oronto
 
Last edited:
This is a picture of my memory tab. It seems to claim (all? ) my dram is running at 1800 Mhz, but I am skeptical. Would this be a case of misreporting?
Your ram is running at 3600mhz (effective).
Actual frequency is 1800mhz. But 2 data transfers per clock give 3600mhz effective frequency.
That's how DDR technology works.

I'd suggest you set Command Rate to 2T.
Running 4 modules with 1T command rate may introduce ram errors.
 
Your ram is running at 3600mhz (effective).
Actual frequency is 1800mhz. But 2 data transfers per clock give 3600mhz effective frequency.
That's how DDR technology works.

I'd suggest you set Command Rate to 2T.
Running 4 modules with 1T command rate may introduce ram errors.

Hi SkyNetRising,
I am mildly aware of the doubling of the mhz, but it is interesting to me that only 2 of my 4 sticks are rated for 1800 mhz (3600 mhz effective). The others are rated for 1600 mhz (3200 mhz).

I am uncertain how to set this command rate to 2T, but thank you for the recommendation. I will look into it.
Thanks again,
Oronto
 
Your ram is running at 3600mhz (effective).
Actual frequency is 1800mhz. But 2 data transfers per clock give 3600mhz effective frequency.
That's how DDR technology works.

I'd suggest you set Command Rate to 2T.
Running 4 modules with 1T command rate may introduce ram errors.
Yes, it IS running at that speed, but it should NOT be possible unless it's been manually configured to run that way as two of those DIMMs have XMP profiles that are 3200mhz, so something is definitely unusual here.

I'd recommend running Memtest86 to verify that the configuration is stable and if it is, well, why look a gift horse in the mouth I guess. You can change the command rate in the advanced settings section of the memory settings in the BIOS. You will need to make sure you have your BIOS view set to the advanced view. The basic or EZ view will not give you access to those settings.

Memtest86


Go to the Passmark software website and download the USB Memtest86 free version. You can do the optical disk version too if for some reason you cannot use a bootable USB flash drive.


Create bootable media using the downloaded Memtest86. Once you have done that, go into your BIOS and configure the system to boot to the USB drive that contains the Memtest86 USB media or the optical drive if using that option.


You CAN use Memtest86+, as they've recently updated the program after MANY years of no updates, but for the purpose of this guide I recommend using the Passmark version as this is a tried and true utility while I've not had the opportunity to investigate the reliability of the latest 86+ release as compared to Memtest86. Possibly, consider using Memtest86+ as simply a secondary test to Memtest86, much as Windows memory diagnostic utility and Prime95 Blend or custom modes can be used for a second opinion utility.


Create a bootable USB Flash drive:

1. Download the Windows MemTest86 USB image.

2. Right click on the downloaded file and select the "Extract to Here" option. This places the USB image and imaging tool into the current folder.

3. Run the included imageUSB tool, it should already have the image file selected and you just need to choose which connected USB drive to turn into a bootable drive. Note that this will erase all data on the drive.



No memory should ever fail to pass Memtest86 when it is at the default configuration that the system sets it at when you start out or do a clear CMOS by removing the CMOS battery for five minutes.

Best method for testing memory is to first run four passes of Memtest86, all 11 tests, WITH the memory at the default configuration. This should be done BEFORE setting the memory to the XMP profile settings. The paid version has 13 tests but the free version only has tests 1-10 and test 13. So run full passes of all 11 tests. Be sure to download the latest version of Memtest86. Memtest86+ has not been updated in MANY years. It is NO-WISE as good as regular Memtest86 from Passmark software.

If there are ANY errors, at all, then the memory configuration is not stable. Bumping the DRAM voltage up slightly may resolve that OR you may need to make adjustments to the primary timings. There are very few secondary or tertiary timings that should be altered. I can tell you about those if you are trying to tighten your memory timings.

If you cannot pass Memtest86 with the memory at the XMP configuration settings then I would recommend restoring the memory to the default JEDEC SPD of 1333/2133mhz (Depending on your platform and memory type) with everything left on the auto/default configuration and running Memtest86 over again. If it completes the four full passes without error you can try again with the XMP settings but first try bumping the DRAM voltage up once again by whatever small increment the motherboard will allow you to increase it by. If it passes, great, move on to the Prime95 testing.

If it still fails, try once again bumping the voltage if you are still within the maximum allowable voltage for your memory type and test again. If it still fails, you are likely going to need more advanced help with configuring your primary timings and should return the memory to the default configuration until you can sort it out.

If the memory will not pass Memtest86 for four passes when it IS at the stock default non-XMP configuration, even after a minor bump in voltage, then there is likely something physically wrong with one or more of the memory modules and I'd recommend running Memtest on each individual module, separately, to determine which module is causing the issue. If you find a single module that is faulty you should contact the seller or the memory manufacturer and have them replace the memory as a SET. Memory comes matched for a reason as I made clear earlier and if you let them replace only one module rather than the entire set you are back to using unmatched memory which is an open door for problems with incompatible memory.

Be aware that you SHOULD run Memtest86 to test the memory at the default, non-XMP, non-custom profile settings BEFORE ever making any changes to the memory configuration so that you will know if the problem is a setting or is a physical problem with the memory.
 
Solution
Yes, it IS running at that speed, but it should NOT be possible unless it's been manually configured to run that way as two of those DIMMs have XMP profiles that are 3200mhz, so something is definitely unusual here.

I'd recommend running Memtest86 to verify that the configuration is stable and if it is, well, why look a gift horse in the mouth I guess. You can change the command rate in the advanced settings section of the memory settings in the BIOS. You will need to make sure you have your BIOS view set to the advanced view. The basic or EZ view will not give you access to those settings.

Memtest86


Go to the Passmark software website and download the USB Memtest86 free version. You can do the optical disk version too if for some reason you cannot use a bootable USB flash drive.


Create bootable media using the downloaded Memtest86. Once you have done that, go into your BIOS and configure the system to boot to the USB drive that contains the Memtest86 USB media or the optical drive if using that option.


You CAN use Memtest86+, as they've recently updated the program after MANY years of no updates, but for the purpose of this guide I recommend using the Passmark version as this is a tried and true utility while I've not had the opportunity to investigate the reliability of the latest 86+ release as compared to Memtest86. Possibly, consider using Memtest86+ as simply a secondary test to Memtest86, much as Windows memory diagnostic utility and Prime95 Blend or custom modes can be used for a second opinion utility.


Create a bootable USB Flash drive:

1. Download the Windows MemTest86 USB image.

2. Right click on the downloaded file and select the "Extract to Here" option. This places the USB image and imaging tool into the current folder.

3. Run the included imageUSB tool, it should already have the image file selected and you just need to choose which connected USB drive to turn into a bootable drive. Note that this will erase all data on the drive.



No memory should ever fail to pass Memtest86 when it is at the default configuration that the system sets it at when you start out or do a clear CMOS by removing the CMOS battery for five minutes.

Best method for testing memory is to first run four passes of Memtest86, all 11 tests, WITH the memory at the default configuration. This should be done BEFORE setting the memory to the XMP profile settings. The paid version has 13 tests but the free version only has tests 1-10 and test 13. So run full passes of all 11 tests. Be sure to download the latest version of Memtest86. Memtest86+ has not been updated in MANY years. It is NO-WISE as good as regular Memtest86 from Passmark software.

If there are ANY errors, at all, then the memory configuration is not stable. Bumping the DRAM voltage up slightly may resolve that OR you may need to make adjustments to the primary timings. There are very few secondary or tertiary timings that should be altered. I can tell you about those if you are trying to tighten your memory timings.

If you cannot pass Memtest86 with the memory at the XMP configuration settings then I would recommend restoring the memory to the default JEDEC SPD of 1333/2133mhz (Depending on your platform and memory type) with everything left on the auto/default configuration and running Memtest86 over again. If it completes the four full passes without error you can try again with the XMP settings but first try bumping the DRAM voltage up once again by whatever small increment the motherboard will allow you to increase it by. If it passes, great, move on to the Prime95 testing.

If it still fails, try once again bumping the voltage if you are still within the maximum allowable voltage for your memory type and test again. If it still fails, you are likely going to need more advanced help with configuring your primary timings and should return the memory to the default configuration until you can sort it out.

If the memory will not pass Memtest86 for four passes when it IS at the stock default non-XMP configuration, even after a minor bump in voltage, then there is likely something physically wrong with one or more of the memory modules and I'd recommend running Memtest on each individual module, separately, to determine which module is causing the issue. If you find a single module that is faulty you should contact the seller or the memory manufacturer and have them replace the memory as a SET. Memory comes matched for a reason as I made clear earlier and if you let them replace only one module rather than the entire set you are back to using unmatched memory which is an open door for problems with incompatible memory.

Be aware that you SHOULD run Memtest86 to test the memory at the default, non-XMP, non-custom profile settings BEFORE ever making any changes to the memory configuration so that you will know if the problem is a setting or is a physical problem with the memory.

Hi DarkBreeze,
Thanks for the help! I will run this test ASAP, although it looks like it may take me a while to figure out how to run it. For the record I do not recall ever manually setting my ram speeds, other than enabling XMP.

Thanks again,
Oronto