[SOLVED] Memory clock/speeds math.

Jul 11, 2019
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So I have a pair of 3200 MHz DDR4 sticks. And I've read somewhere that when I have 2 sticks, they're each split I'm half and should be like 2x 1600 MHz? Though I am only able to get my RAM to run at 1300 MHz each, before my system gets unstable. And it's set to 1067 MHz by default? Why is that, and should they be set to 1600 MHz each by default? Or is this something XMP related?
 
So I have a pair of 3200 MHz DDR4 sticks. And I've read somewhere that when I have 2 sticks, they're each split I'm half and should be like 2x 1600 MHz? Though I am only able to get my RAM to run at 1300 MHz each, before my system gets unstable. And it's set to 1067 MHz by default? Why is that, and should they be set to 1600 MHz each by default? Or is this something XMP related?
That would be something I never heard of (unless it's some weird laptop).
You must be confused with fact that it's DDR (double Data Rate) and some programs and OS may show only half speed i which case you should multiply such result by 2 to get real speed.
Don't know what your hardware is but some MBs limit the highest frequency.
 
Jul 11, 2019
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That would be something I never heard of (unless it's some weird laptop).
You must be confused with fact that it's DDR (double Data Rate) and some programs and OS may show only half speed i which case you should multiply such result by 2 to get real speed.
Don't know what your hardware is but some MBs limit the highest frequency.
It's a PC.
GTX 1060 6 gb
Ryzen 5 2600
Mobo: MSI B450m pro m-2
RAM: Patriot Extreme Performance Viper 4
DDR4, 16 GB: 2 x 8 GB, DIMM 288-PIN, 3200 MHz / PC4-25600, CL16, 1.35 V,

I figured out the fact that I have to multiply by two, but I am only able to get it working on 1333 MHz each (2666 MHz effectively) but the ram is advertised as 3200. So I should be able to run 1600 MHz x2?
 
Jul 11, 2019
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full system spec?
GTX 1060 6 gb
Ryzen 5 2600
Mobo: MSI B450m pro m-2
RAM: Patriot Extreme Performance Viper 4
DDR4, 16 GB: 2 x 8 GB, DIMM 288-PIN, 3200 MHz / PC4-25600, CL16, 1.35 V,
BTW I achieved the 1333 MHz on each without modyfing voltage or timings.
 
It's a PC.
GTX 1060 6 gb
Ryzen 5 2600
Mobo: MSI B450m pro m-2
RAM: Patriot Extreme Performance Viper 4
DDR4, 16 GB: 2 x 8 GB, DIMM 288-PIN, 3200 MHz / PC4-25600, CL16, 1.35 V,

I figured out the fact that I have to multiply by two, but I am only able to get it working on 1333 MHz each (2666 MHz effectively) but the ram is advertised as 3200. So I should be able to run 1600 MHz x2?
Doesn't XMP work ?
 
DDR stands for (D)ouble (D)ata (Rate). This is implemented by transferring data on both the rising and falling edge of the clock signal. This holds true no matter how many modules you are using. So your clock rate of 1333 gives you 2666 effective ram speed.

Each memory module (stick) has a 64 bit wide data bus. A dual channel system will make 2 of those modules appear to be 128 bits wide. So twice as much data is transferred at a time.

It doesn't matter what speed the ram is rated for. It's only going to run as fast as the motherboard and CPU will allow. Looking at the specs here that is as fast as it will run without overclocking which, with an Intel CPU, is called XMP. You'll see higher speeds in the specs but since they are considered overclocking there is no guarantee that the installed RAM will run at the higher speeds. Overclocking, by definition, is working outside the guaranteed specifications. Otherwise, it wouldn't be overclocking. It may work but it's not guaranteed to work.

You are getting the highest guaranteed speed out of the ram. You'll need to experiment with XMP to get anything faster which might or might not happen.
 
Jul 11, 2019
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DDR stands for (D)ouble (D)ata (Rate). This is implemented by transferring data on both the rising and falling edge of the clock signal. This holds true no matter how many modules you are using. So your clock rate of 1333 gives you 2666 effective ram speed.

Each memory module (stick) has a 64 bit wide data bus. A dual channel system will make 2 of those modules appear to be 128 bits wide. So twice as much data is transferred at a time.

It doesn't matter what speed the ram is rated for. It's only going to run as fast as the motherboard and CPU will allow. Looking at the specs here that is as fast as it will run without overclocking which, with an Intel CPU, is called XMP. You'll see higher speeds in the specs but since they are considered overclocking there is no guarantee that the installed RAM will run at the higher speeds. Overclocking, by definition, is working outside the guaranteed specifications. Otherwise, it wouldn't be overclocking. It may work but it's not guaranteed to work.

You are getting the highest guaranteed speed out of the ram. You'll need to experiment with XMP to get anything faster which might or might not happen.
Found this on my motherboards info site
  • Supports DDR4-3466(OC) Memory
Says OC, so I guess I need to use xmp?
 
Jul 11, 2019
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DDR stands for (D)ouble (D)ata (Rate). This is implemented by transferring data on both the rising and falling edge of the clock signal. This holds true no matter how many modules you are using. So your clock rate of 1333 gives you 2666 effective ram speed.

Each memory module (stick) has a 64 bit wide data bus. A dual channel system will make 2 of those modules appear to be 128 bits wide. So twice as much data is transferred at a time.

It doesn't matter what speed the ram is rated for. It's only going to run as fast as the motherboard and CPU will allow. Looking at the specs here that is as fast as it will run without overclocking which, with an Intel CPU, is called XMP. You'll see higher speeds in the specs but since they are considered overclocking there is no guarantee that the installed RAM will run at the higher speeds. Overclocking, by definition, is working outside the guaranteed specifications. Otherwise, it wouldn't be overclocking. It may work but it's not guaranteed to work.

You are getting the highest guaranteed speed out of the ram. You'll need to experiment with XMP to get anything faster which might or might not happen.
Also from the link with the specs you sent me, it looks like 3200 MHz should work without xmp?
 
Im pretty sure that I tried it, and it wouldn't boot. Also for me it's called A-XMP. What do you recommend?
It's also called DOCP with some AMD products but it essentially has to follow XMP in the memory.
You can start by setting A-XMP to XMP setting and start by setting frequency and gradually increase it after every restart. Some call it Memory Training.
This is a handy tool if you want to try manual settings https://www.techpowerup.com/download/ryzen-dram-calculator/
 
Jul 11, 2019
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It's also called DOCP with some AMD products but it essentially has to follow XMP in the memory.
You can start by setting A-XMP to XMP setting and start by setting frequency and gradually increase it after every restart. Some call it Memory Training.
This is a handy tool if you want to try manual settings https://www.techpowerup.com/download/ryzen-dram-calculator/
Well in A-XMP I have to profiles.
2933MHz 16-18-18-36
And 3200 MHz 16-18-18-36
 
Jul 11, 2019
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It's also called DOCP with some AMD products but it essentially has to follow XMP in the memory.
You can start by setting A-XMP to XMP setting and start by setting frequency and gradually increase it after every restart. Some call it Memory Training.
This is a handy tool if you want to try manual settings https://www.techpowerup.com/download/ryzen-dram-calculator/
Thanks for the help, managed to get it working. I got the manual page for my ram, which had the tested timing for 3200 mhz. I matched them in bios and now I got them working on 1600 MHz each.
 
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