XMP 2 may provide more stability at the DIMMs default timings. Use XMP 1 if not experiencing any instability issues, this is the profile validated by ASUS.
I have the same setup and same issues. Updated to latest 904 Bios with no change. I have however been able to get XMP1 and XMP2 working by dropping down to just 2 dimms for a total of 64gig of ram. Hoping for a bios update in the future that addresses this issue. Running 64 gig ram at the full 6400 mem speed. So its a trade off. 128gig at slower speeds, or 64gig full throttle.
Cheers and good luck!
Experienced memory overclocker here. I think i might be able to help. *knocks on wood*. In your bios where it gives you the option to enable xmp, is there a feature that says "manual"? If so, select manual instead of xmp. Then set the frequency to 6400mhz. Then manually set the primary timings to 32-38-38-100 instead of 32-39-39-102. Make sure you set command rate to 2T. Manually set your ddr vddq voltages both to 1.4v and set the IVR vddq voltage to 1.4v. Manually set both the system agent voltage and the memory controller voltage both to 1.3v each. Try to boot. If it doesn't boot, try setting both the system agent voltage and the memory controller voltages each to 1.35v. See if it boots. If it doesn't boot, reset your cmos and try using 32-38-38-101 for the primary timings while starting at 1.3v system agent voltage + 1.3v memory controller voltage to start. See if it boots. If not, try 1.35v system agent voltage and 1.35v memory controller voltage. These suggestions are based off of myself and other users having to set slightly tighter timings(32-38-38 instead of 32-39-39) to get ddr5 6400mhz 32-39-39 kits to work at the rated speed on various platforms.
Please let me know how it turns out.
Thanks for the fix info. I however am not highly experienced in overclocking so will take some digging and research to establish these settings. Some are self explanitory, others however are a bit confusing ie. I was able to find 2N command rate but not 2T. Not looking for hand holding through this process, but will give it a try and keep you posted.
I use a Strix ROG z790H with Trident z5 RGB @6000 mhz CL30 and I have 64G total 16Gx4. Using with 13700k. I built this around 4-5 months ago but I've not had issues. My ram is made for the 6k OC so I use xmp 1 and an offset voltage 0.13000 and my P cores are between 5.2 & 5.4. , E cores 4.1 & 4.2. Even before my offset voltage tweaks xmp 1 @6k worked fine. Hopefully you found a solution to this. I would be extremely upset. I would write a letter to Asus and demand a fix or swap for maybe a z790H like I have. I believe it's almost same price (I paid $299) But I'd most definitely send a few detailed emails to asus and tell them I'm upset and I've been a customer many years and I know many people and I will write reviews as I always do about ny experience with this. Please let me know something about this at your earliest convenience. Thanks for your time. Please don't not reply to this. I've heard many negative things about Asus recently and this is the first time I've had issues. I don't want to be another person who adds to the negativity that Asus has gotten recently but if this isn't answered and something isn't done to resolve it soon I'll have no choice but to speak openly about my experience. Thanks for your time. I believe sometimes it's how you communicate with people that may or may not get you what you are needing resolved. I know I've been on the other side of things similar before where I had people tell me they weren't pleased with this or that and I always tried to do what I could but there were times where some people were rude and others were more respectful at communicating with me and I was definitely more inclined to helping the people who talked to me in a detailed not aggressive way. When someone has a bad experience and doesn't write a review about anything if they never got whatever resolved that's not good. I believe everyone should write about such experiences but when people come off as aggressive sometimes that can cause said customer to not get the help that they need.
My first thoughts when reading your op was bios update. Hopefully you're good now. If not I'd be asking for a z790H Strix ROG board. If I was ignored or it didn't get resolved I would express my feelings in a detailed manner on a few known sites and write them a few letters.