ROG Maximus Z790 Extreme with 128GB Corsair Dominator Memory OC

[Old_School]

Hi,

Does anyone know if its possible to OC the ROG Maximus Z790 Extreme with 128GB Corsair Dominator Memory? The OC in the BIOS (ROG-MAXIMUS-Z790-EXTREME-ASUS-1202) seems to work on the processor which is an Intel i9-13900KS and will run at 6GHz, but the memory which normal speed is meant to be 5600MHz will only run at 4800MHz according to Windows 11 Pro

When I try the XMP1 or XMPII OC profiles in the BIOS, the Windows will not load and the motherboard displays a 55 error code. The memtest has passed the memory, so it's not the memory itself.

My question is, is there any way to OC the Maximus Z790 Extreme with all 4 DIMM slots populated with 128GB memory? If so, can someone please provide the configuration settings?

Thanks in advance

Old_School

[Silent_Scone]

Hello and welcome, could you specific which memory kit?

[Old_School]

Hi Silent_Scone, 

The memory kit I an using is 2 * Corsair Dominator Platinum RGB DDR5 RAM 64GB (2x32GB) 5600MHz CL40 Intel XMP iCUE Compatible Computer Memory - Black (CMT64GX5M2X5600C40).

Suppose to be able to OC up to 72OOMHz

[Silent_Scone]

It is not recommended to combine or mix memory kits. The XMP profile is validated in the density in which the memory vendor sells them. 128GB @ 7200MT is not possible on this platform.

Have you attempted to run XMP with one kit installed?

[Old_School]

No, i have not tried with 64GB. I was looking for the 128GB memory to run at 5600MHz rather than 4800MHz. I'll wait for a future BIOS update that may improve the memory performance

Thanks Silent_Scone for your reply and information. 

[Silent_Scone]

No worries. It’s not likely that a BIOS update will help you with combining these two kits without manual tuning. They are not binned to run at the specified frequency, voltage and timings when ran together. Your best bet would be to return both and purchase a single 128gb kit rated at 5600MT

[Daedube]

I have the same corsair kit 2x2x32 trying to get 128gb to be stable with no errors. Were you ever able to find a solution for this? how did you set it up in the bios? 

[naulito]

Apparently, at the moment there is no way to be able to use 128GB of RAM on Z690 and Z790 in a stable way and using XMP profiles. There are crashes, BSOD or simply the pc does not post.

Stability of your RAM at OC speeds depends on the lottery quality of your CPU. This is a known fact as the memory controller is on the CPU.

If you buy 2 KITS of RAM memory, even though it seems that they are identical, they are not, at the manufacturing and chip level they are not the same. That is why, in theory, if it were possible to use 128GB of RAM, it would only be by buying a memory KIT that contains the 4 RAM modules together and in a single package and they practically don't exist, except for the A-Tech 128GB (4x32GB) DDR5 4800MHz kit without XMP profiles.

Look for this video on Youtube with J.J from Asus. It will solve practically all your doubts: Why I get NO POST with XMP??? 👉 ULTIMATE RAM + XMP Guide

[Silent_Scone]

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@naulito wrote:

If you buy 2 KITS of RAM memory, even though it seems that they are identical, they are not, at the manufacturing and chip level they are not the same. That is why, in theory, if it were possible to use 128GB of RAM, it would only be by buying a memory KIT that contains the 4 RAM modules together and in a single package and they practically don't exist, except for the A-Tech 128GB (4x32GB) DDR5 4800MHz kit without XMP profiles.

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This isn't accurate. The challenges of buying matched kits isn't an issue due to manufacturing differences. In fact, it's very likely the two kits will be the same memory IC and revision if bought simultaneously.

The challenges are this:

Firstly one needs to understand what binning is. If you don't, then there's likely some knowledge gaps there also. In laymans terms this is the process the memory vendor would use to find memory modules capable of achieving a certain overclocking milestone. E.g. 6200MT, CL36-36-36-96 @ 1.35v

Imagine you are G.SKILL. You have stacks of PC5-4800 to test. You're binning for 6200MT in a 32GB kit with 2x16GB DDR5 modules.

The timings need to be reasonable enough that G.SKILL is able to bin enough of these kits to sell them. The target is to ensure there is a significant guardband in place that these two modules will operate @ 6200 in a qualified motherboard in that density, at the memory vendor's designated timings, voltage and frequency.

Most enthusiasts will know that higher memory densities are harder on the CPU memory controller when we increase memory frequency. This is no different for the memory modules themselves. As soon as we add two additional DIMMs into the system regardless if they're the same part number, G.SKILL, ASUS or the user has no way of knowing if that kit will still be able to achieve 6200MT at the same voltage or timings without manual adjustment - or in most cases at all - because they were never tested to run in 4x16GB configuration at these settings.

Basically, you're on your own.

@ 128GB buying a single kit is essential. Do not mix kits!