Question Memory upgrade with same modules fail

[qCasau]

Hi all,

I have just upgraded my computer with 2 new memory modules. They are the same as the 2 first I already had : Kingston Fury Beast DDR5 5200 2x16GB.
So I have now 64 GB on my mother board ASRock Z690 PG Velocita.

Before the upgrade, in the BIOS, the only parameter that was manually set regarding the memory is : "Load XMP settings" -> "XMP 3.0 profile 1"
After installing the new memory modules, the system wouldn't boot. I had to update the BIOS to be able to boot. It then worked normally without any change in the BIOS parameters (keeping the XMP profile).
But I noticed in windows task manager that my memory modules were running at 2000 MHz instead of 5200 MHz. The system was working and stable.

Back in the BIOS I noticed that the BIOS showed my memory as "DDR5-2000". I then changed the parameter "DRAM Frequency" from "Auto" to "DDR5-5200".
It works and the task manager now shows 64GB of memory at 5200 MHz.
But the system is unstable and crashes after 5 minutes of gaming (brief frozen screen and reboot).

The first 2 memory modules were bought in 2022 and the last ones in 2023. The BIOS can show memory modules details and it shows notable diffences beetween the first 2 and last 2 : manufacturing dates (2022 vs 2023) and PMIC revision (36 vs 44).

Here is the config in details :
MotherBoard : ASRock Z690 PG Velocita
MotherBoard web page : https://pg.asrock.com/MB/Intel/Z690 PG Velocita/index.us.asp#Manual
Memory : 4x16GB Kingston Fury Beast KF552C40BBK2-3
Memory data sheet : https://www.kingston.com/datasheets/KF552C40BBK2-32.pdf
Processor : i5-12600K

Is it because the modules are slightly different that the computer is crashing or is there some settings to be adjusted in the BIOS ?

Thank you for your help !

 

[qCasau]

And I have just noticed another important difference between the memory modules :
"DRAM Manufacture" is "Samsung" for the old ones and "Hynix" for the new ones...

 

[kanewolf]

And I have just noticed another important difference between the memory modules :
"DRAM Manufacture" is "Samsung" for the old ones and "Hynix" for the new ones...

You have run into the "same memory" isn't really the same. Manufacturers sell matched sets for a reason. They test ALL the DIMMs as a set.
I would set the memory to "Auto" to start with. See if you can get the RAM to run stable with MEMTEST86 for 4+ hours. If so, then see if you can get them to a faster speed.

 

[qCasau]

Thanks for your help !

I followed your advise and get the RAM stable until 4400 MHz.

I then tried the 2 new modules only and they work nice and stable @5200MHz.
So the new modules work just as good as the old ones, but the 4 of them don't.

I will send back the new modules for "incompatibility" and try to get refund.

Thanks again for your time !