Severe Instability Issues with V-Color Manta DDR5-7800 Modules on i9-14900K and Z790 Maximus Hero

[jftuiran]

Hi everyone,

I hope you’re doing well! I wanted to share my experience and hopefully get some advice, because I’m honestly at a loss with my current setup.

**My system:**
- Intel Core i9-14900K (using only the integrated graphics)
- ASUS Z790 Maximus Hero (latest BIOS)
- 4 x 24GB V-Color Manta DDR5-7800 (96GB total, all from the same kit)
- 4TB SSD (no issues here)
- Windows 11 Pro (fresh install, all drivers up to date)

**Here’s what’s been happening:**
- From the start, I never enabled the XMP profile for 7800MT/s—actually, I never even tried running the RAM above 5600MT/s. I always kept things at default or auto, just to keep things safe.
- With all four sticks at 5600MT/s, the system would boot, but Windows was super unstable: blue screens, memory errors, you name it.
- I tested each stick one by one. Some seemed a bit more finicky than others, but there wasn’t a clear “bad module.”
- I decided to just run two sticks at 5600MT/s, and for about a week, everything was smooth—no crashes or weirdness.
- Then, after leaving the PC on overnight, I woke up to artifacts all over the screen. After rebooting, Windows wouldn’t even load unless I left just one stick of RAM in.
- Now, no matter which slot or module I use, the PC only works with a single stick. It’s honestly baffling and a bit frustrating!
- When I first built the system, I ran MemTest86, Windows Memory Diagnostic, Intel Processor Diagnostic Tool, and more. Everything was perfect—no errors at all.
- The weird part is, all these problems only started after about a week of normal use.
- The SSD is fine—never had any issues there.

**What I’ve tried so far:**
- Swapping modules and slots
- Running everything at default/auto, never overclocking or enabling XMP
- Multiple rounds of stress tests (initially and after problems started)
- BIOS is fully updated

**My questions:**
1. Has anyone else had similar issues with the i9-14900K’s memory controller when using high-capacity V-Color DDR5-7800 kits, even at lower speeds like 5600MT/s?
2. Could this be a sign of the memory controller (IMC) degrading? I’ve seen a few stories online, but I’m not sure.
3. What would you recommend to really confirm if it’s the CPU’s memory controller, the RAM, or maybe the motherboard?
4. Should I go ahead and RMA the CPU, or is there something else I should try first?

I’d really appreciate any advice or ideas you might have. Thanks so much for taking the time to read my post!

[ArchieD_Intel]

Hi jftuiran,

Thank you for reaching out to the Intel Community Forum. To assist us in investigating the issue, please provide the following details:

• When did the issue start?
• Did you overclock the processor?
• Did you apply the Intel Default Settings?
• Is there any physical damage?

Additionally, to gain a comprehensive understanding of your system, please use the System Support Utility (SSU). This tool will generate a text file compiling all your system information. You can follow the instructions at this link and send the text file here. Help Guide for the Intel® System Support Utility.

If you have any questions, please let us know. Thank you.

Best regards,

Archie D.

Intel Customer Support Technician

[jftuiran]

Hi Archie,

Thank you for your reply and for guiding me through the troubleshooting process.

Here are my answers to your questions:

When did the problem start?
The issue began during the very first week after assembling the system. I started experiencing blue screens and system instability almost immediately after initial setup.
Additionally, from the very first boot, the system would not accept any XMP profiles for the memory. Because of this, I left the memory running at the base frequency of 4800MT/s.

Did you overclock the processor?
No, I never overclocked the processor. All BIOS settings have always been left at their default values.

Did you apply Intel’s default configuration?
Yes, the entire system was assembled and configured using only the default settings in the latest available BIOS. No custom or manual adjustments were made.

Is there any physical damage?
There is no physical damage to the CPU. It was taken directly from the box and installed into the socket by qualified technicians.

Additionally, I have attached the TXT file generated by the Intel System Support Utility (SSU) as requested, to provide a comprehensive overview of my system.

At this moment, the PC will not boot with all four RAM modules installed. I am currently running the system with only one module, as adding any of the other three causes the system to either get stuck in a reboot loop or display memory-related error codes on the motherboard. This issue persists regardless of which modules or slots are used.

Please let me know if you need any more information or further tests. I appreciate your help and look forward to your recommendations.

Best regards,
jftuiran

[ArchieD_Intel]

Hi jftuiran,

I wanted to check if you had the chance to review the questions I posted. Please let me know at your earliest convenience so that we can determine the best course of action to resolve this matter. 

Best regards,

Archie D.

Intel Customer Support Technician

[jftuiran]

Hi Archie,

Thank you very much for following up and for your patience.

I apologize for the delay in my response. I have now reviewed your questions and provided detailed answers, along with the requested SSU report, in my previous message. Please let me know if you need any additional information or if there are further steps I should take.

Thank you again for your support and understanding.

[ArchieD_Intel]

Hi jftuiran,

Thank you for your update and providing the requested information.

Please check your email inbox, as we have sent you a message regarding our concern.

Thank you and have a great day ahead!

Best regards,

Archie D.

Intel Customer Support Technician

[jftuiran]

Hi Archie,

Thank you very much for your help and for the information provided.
I wanted to let you know that I have already replied to your message via email.

I appreciate your support and remain attentive to any updates!

Best regards,