Memory Training

[neufuse Veteran]

So I upgraded one of my systems from 64GB to 128GB (yes I have a reason, I was using more than 64GB for dev) and now I'm seeing some oddness

I have an ASUS ROG Strix Z790-A board with a 13900k in this system. When I change the XMP profile of the old 64GB (16x4) memory so it's running at 6000MTs it works fine and doesn't memory train at all it feels like, first boot after the change is within seconds.

The new 128GB memory is also 6000MT/s with Intel XMP profiles also, but on first boot with default BIOS settings it takes 5 minutes to start with memory training, that's a major difference for the base 4200MT/s setting.. Change it to XMP and it now takes 20 minutes to memory train.

Anyone else ever see this? I know memory training can take a while sometimes but this seems like a lot compared to the old memory..

 

I also ran into an odd issue when it's switched to 6000 MT/s speed when windows boots it complains that the GPT header is corrupt on the drive and needs fixed... when you switch back to 4200 it works fine... MemTest in the UEFI bios claims the ram is fine and working right. the old ram ran fine in this system at 6000. The motherboard claims it supports both memory modules I am using.

Edited Thursday at 17:55 by neufuse

[+Warwagon MVC]

  On 27/03/2025 at 17:50, neufuse said:

So I upgraded one of my systems from 64GB to 128GB (yes I have a reason, I was using more than 64GB for dev) and now I'm seeing some oddness

I have an ASUS ROG Strix Z790-A board with a 13900k in this system. When I change the XMP profile of the old 64GB (16x4) memory so it's running at 6000MTs it works fine and doesn't memory train at all it feels like, first boot after the change is within seconds.

The new 128GB memory is also 6000MT/s with Intel XMP profiles also, but on first boot with default BIOS settings it takes 5 minutes to start with memory training, that's a major difference for the base 4200MT/s setting.. Change it to XMP and it now takes 20 minutes to memory train.

Anyone else ever see this? I know memory training can take a while sometimes but this seems like a lot compared to the old memory..

 

I also ran into an odd issue when it's switched to 6000 MT/s speed when windows boots it complains that the GPT header is corrupt on the drive and needs fixed... when you switch back to 4200 it works fine... MemTest in the UEFI bios claims the ram is fine and working right. the old ram ran fine in this system at 6000. The motherboard claims it supports both memory modules I am using.

Expand  

First off welcome to the 128GB club.

I doubt the issue I was having has anything to do with your issue. But I Thought I would link it to you just in case.

 

[goretsky Supervisor]

Hello,

A few things to check, in no particular order:

• DDR5 is currently the latest consumer memory technology.  The more memory modules that are installed, the lower the effective RAM speed is going to be.  Remember, by going from two to four DIMMs, you've just doubled the number of electrical signals for the memory subsystem.  And that doesn't get into noise, reflection, and other issues that can affect the integrity of the signal.  I would suggest trying 4800, 5200, and 5600 MT/s speeds to see if these work any better for you?
• Are you using the same brand and model of memory in all four slots?  If not, there could be some additional time required to negotiate the various timings (CAS, RAS, tCL, etc.) for the memory modules to find ones that work across all four modules.
• Have you tested each stick individually for errors using something like MemTest86+ or MemTest86 (the free version is adequate for this purpose) ?  I know you mentioned running MemTest from the UEFI, but I would suggest running one of these programs overnight from a USB flash drive and see if either identifies any problems.  Sometimes it can take a long time for memory errors t show up.
• Do you have the latest BIOS (UEFI) firmware installed for the ROG STRIX Z790-A GAMING WIFI motherboard?

Hopefully that will allow you to help narrow things down.

Regards,

Aryeh Goretsky
 

[Circaflex]

if you want to skip it all together, look for Memory Context Restore and enable it.