Question Computer Keeps Overriding XMP Profile

[Cathaldus]

Hi there,

My motherboard is ASROCK B450M Pro and the manual advises that it supports quad channel.

I used to be able to run memory at 3200 GHZ with 2 sticks with the XMP Profile, however, now after adding 2 of the same exact ram sticks to have 32GB of RAM at 3200MHz it keeps resetting to 2133MHz.

Any ideas why this is happening?

 

[kerberos_20]

it means either your CPU cant handle XMP profile on four sticks (higher strain on memory controller) or those stick doesnt have working overclocking profile (XMP) with four sticks

you can always fallback to manual ram overclock, right?

 

[Cathaldus]

I will have to try a manual overclock, it's weird because they are base 3200 speed but go down to 2133mhz

 

[kerberos_20]

base 3200 rams have CL like 22 or so, i doubt thats your rams there

if they fall to 2133, then thats their base

 

[Cathaldus]

My bios is updated to the latest, and my cpu is AMD Ryzen 5 2600 as well

 

[kerberos_20]

My bios is updated to the latest, and my cpu is AMD Ryzen 5 2600 as well

With this cpu 2666mhz should work with four sticks

 

[Cathaldus]

https://valid.x86.fr/h5uhty


I will try 2666mhz, thank you!

 

[kerberos_20]

here found original ram support for 2nd gen ryzen

2nd Gen AMD Ryzen Supported RAM Speeds

Just like the original Ryzen CPUs, the 2nd Gen Ryzen processors from AMD support a range of different RAM speeds depending on a number of factors. This information is not easily accessible to the public, however, so we decided to put together a quick post with the information we received from...

www.pugetsystems.com

that post is old, agesa updates got some ram improvements since then, but i wouldnt expect running it higher then 2666

 

[Roland Of Gilead]

here found original ram support for 2nd gen ryzen

2nd Gen AMD Ryzen Supported RAM Speeds

Just like the original Ryzen CPUs, the 2nd Gen Ryzen processors from AMD support a range of different RAM speeds depending on a number of factors. This information is not easily accessible to the public, however, so we decided to put together a quick post with the information we received from...

www.pugetsystems.com

that post is old, agesa updates got some ram improvements since then, but i wouldnt expect running it higher then 2666

Exactly, CPU only supports 2666mhz on 4 DIMMs. Whilst some chips can go higher, it's a bit of a lottery. (IMC silicon lottery) Supported speeds are all you are guaranteed.

Ideally you want a 4 x matched kit. Even mixing DIMMs which are identical in all specs with those from another kit with the same spec, there's no guarantee.

 

[Cathaldus]

Okay, I tried 2933 and it reset.. so I will try 2666.

Does the voltage still have to be 1.35? or should I just put try to put XMP with 2666?

 

[Roland Of Gilead]

Okay, I tried 2933 and it reset.. so I will try 2666.

Does the voltage still have to be 1.35? or should I just put try to put XMP with 2666?

Check the speed tab in CPU-z and choose the corresponding voltage for 2666mhz if it's stated. If not, 1.35v

 

[Roland Of Gilead]

My bios is updated to the latest, and my cpu is AMD Ryzen 5 2600 as well

Did you clear CMOS after the bios update? This could help, if you haven't already.

 

[Cathaldus]

https://imgur.com/a/s6mA1gu

View: https://imgur.com/a/s6mA1gu


So This is my speed tab after setting to xmp and 2666MHz.

Is this safe or should I swap it to 1.2v?

 

[Cathaldus]

Did you clear CMOS after the bios update? This could help, if you haven't already.

No I never cleared CMOS

 

[Cathaldus]

Task Manager shows 2667MHz now, and it didnt go through the three checks though

 

[Roland Of Gilead]

No I never cleared CMOS

Do that. It will clear any remnants of microcode or settings from the last bios.

 

[Roland Of Gilead]

https://imgur.com/a/s6mA1gu

View: https://imgur.com/a/s6mA1gu


So This is my speed tab after setting to xmp and 2666MHz.

Is this safe or should I swap it to 1.2v?

You can try it with 1.2v. Test it with memtest86+ or Windows Mem Diagnostic to ensure they run okay at that speed. If so, you are good to go. You can go up in increments of 0.05mv. So try 1.2, then 1.25 etc until DIMMs are stable.

 

[Cathaldus]

The interesting thing now is I just got it to get to 2800MHz after a reset.

 

[Karadjgne]

Zen, Zen+, Zen2 cpus do Not like 4 sticks. At all. It's a memory controller limitation to do with the infinity fabric.

Zen+ cpus are pretty much good to get 2933MHz with 4x sticks, very few get the full 3200MHz and that normally requires not only ram voltage tweaking, as high as 1.4v, but also setting SOC voltage to 1.2v maximum as well as possibly relaxing some timings.

Out of those capable of stability at 3200MHz with 4x sticks on Zen+, almost all are Samsung B-die OEM, very rarely Micron D-die, and SkHynix is outta luck afaik.

 

[Roland Of Gilead]

The interesting thing now is I just got it to get to 2800MHz after a reset.

It's possible the new bios gave more stability with SOC voltage and maybe why it's working at 2800 as opposed to the 2666 max supported for 4 DIMMs.

Well, that's good! It's another strap higher than before, so will still bring some benefit over 2666mhz, even though it's not that much of a difference in real terms.