Asking about stable XMP on quad channel DDR5 Z790 Asus TUF Plus Wifi

[Tweakerstarter]

Hello fellow Asus users,

I am currently running into issue of not passing RAM test when boot with XMP on. I am running on Dual Chanel with 2 identical Gskill kit at 6400mhz the only different is one of the memory kit if 32Gbx2. I could not OC the RAM to upper than the system auto setting  non XMP 4200Mhz. Everytime I turn the xmp on for whatever XMP I chose and even with the SVID DRam voltage set up from basic 1.4v to 1.41 or 1.42 it would not boot and pass the memory test, if I restart then boot I got BSOD and Unexpected Kernel Mode Trap error. I would not know how to set this to work and how to run 4 RAM at 96GB to work. If I only install in Slot A2 And B2 it would work normal with XMP on. Additionally to boot the pc with the default RAM speed I have to clear the CMOS by removing the battery to make 4 RAM sticks work.

Ps: I am using the 14900K with newest BIOS update on 10.24.2024 from Asus suppory site

Could some professional or acknowledge people know how to make this work I really appreciated that.

[Silent_Scone]

Hi @Tweakerstarter 

The best advice anyone can give you is to purchase a kit from the QVL at the density you wish to run.

Combining and mixing memory kits isn't supported by memory or motherboard vendors. If you combine memory kits, the overclocked settings in which the kit is validated for XMP/EXPO are no longer valid. Purchase a single kit validated for the density and you are trying to run from the QVL (even then there can be concessions depending on the frequency and CPU). This is because memory vendors bin and validate the memory kit in the density in which it is sold. Whether we combine a kit with the same part number, frequency, timings or voltage the advice remains the same.

Key Points on Why Not to Combine Memory Kits:

Mismatched Timings and Density:

• Memory vendors bin kits at specific densities.

• Combining kits for higher density invalidates programmed timings, leading to potential issues.

Troubleshooting Challenges:

• If rated timings fail, tuning the system manually becomes necessary.

• Manually tuning with combined or mixed kits requires a deep understanding of memory timings, posing challenges and technical considerations that are difficult to simplify if not experienced in memory overclocking.

Time-Consuming Tuning Process:

• Tuning memory settings demands significant time, a systematic approach, and patience.

• Lack of knowledge of memory timings complicates the tuning process.

Recommendation for Simplicity:

• Purchase a single, compatible memory kit which is one to three frequency bins below the maximum validated speed on the QVL for a smoother experience.

Outside of JEDEC specification, all overclocking parameters defined by the memory vendor are invalidated when adding more memory to the system. If anything, it can be easier to start from scratch, which is a minefield for anyone not experienced with memory overclocking, or in some cases even those with some experience, more so when it pertains to higher densities.

[Tweakerstarter]

Thank you for your suggestion.

Apparently tuning the timing for 4 RAM sticks are complex and making them run at the motherboard support speed non XMP is time consunming and almost get you not the most out of it.

[Nate152]

Are you able to boot to the bios or windows with 4800MHz?

If you can take a screenshot of the primary timings, we can give you some looser timings to try.

If in the bios, hit the F12 key and save the screenshot to a usb flashdrive.

Or, in windows take a screenshot of the primary timings with CPU-Z or HWinfo. I'd like to know what the primary timings and command rate are currently set to.

As an example, here is HWinfo, click the pic to make it bigger.

[Tweakerstarter]

The highest frequency which is automatic optimize by BIOS now is 4200Mhz and I still have to deal with first boot failure after I updated the newest BIOS. Then a restart made the computer booted up normal. I will try to screenshot timing. As long as I put on XMP it will not pass Mem check.