ROG STRIX X670E-E Gaming WiFi - Critical Boot Failure with Ryzen 9950X3D After Initial Success

[iSentinels]

System Specifications
- Motherboard: ROG STRIX X670E-E Gaming WiFi
- CPU: AMD Ryzen 9 9950X3D
- RAM: 96GB (2x48GB) DDR5-6000 CL30-36-36-96 G.Skill Trident Z5 Neo
- PSU: Corsair RM1000X (1000W)
- BIOS Version: Currently 3003 (downgraded from 3112 to 3104, then down to 3003)
- Build Date: Yesterday (new build)

Issue Description
Brand new system experiencing complete boot failure - cannot even access BIOS. The system briefly worked yesterday after initial troubleshooting, but now fails to POST entirely.

Timeline of Events:
1. Initial build - System wouldn't POST with BIOS 3112
2. First fix attempt - Downgraded to BIOS 3104 via FlashBack, applied some tweaks, system booted successfully into Windows
3. Working period - Installed Windows updates, chipset drivers, and other drivers. System remained stable through multiple restarts
4. Left for 2 hours - System was still running
5. Current state - Complete failure. System powers on briefly then shuts down and attempts to restart. Occasionally can reach BIOS, then saving and exiting (making no changes) causes RAM Q-Code 15 reboot loop. Has also restarted in BIOS.

Troubleshooting Already Attempted
- BIOS FlashBack to version 3104 (worked initially)
- CMOS reset via rear I/O button
- Complete CMOS clear (battery removal + power drain)
- Tested with single RAM stick in A2 slot
- Reseated all RAM modules
- Reseated CPU (checked for bent pins - all good)
- Attempted another BIOS FlashBack
- All overclocking disabled (RAM running below rated speed)
- Verified PSU connections

Current Symptoms
- System powers on for a few seconds
- Sudden shutdown followed by automatic restart attempt
- No display output at any point
- Cannot access BIOS consistently
- Q-Code: Stuck on 15 (Memory Training)
- System appears to be failing memory training and rebooting

Additional Information
- No overclocking applied at any point
- RAM was not even running at its rated 6000MHz speed
- System was completely stable when it was working
- The failure occurred after installing AMD chipset drivers
- Currently attempting to flash older BIOS versions
- Removed SSD. No GPU currently in system. Still cannot boot.

Questions
1. Which BIOS version is most stable for 9950X3D with 96GB RAM configuration?
2. Are there known issues with chipset drivers causing boot failures on this board?
3. Is there any specific BIOS I should be using?
4. Any specific settings for 96GB (2x48GB) configurations?

Any guidance would be greatly appreciated as I cannot even reach BIOS consistently to make changes.

[iSentinels]

Additional Info:

I’ve since tried plugging in a 16gb ddr5 6000 cl36 stick from a friend - and it’s having the same issues. It was getting to the “updating bios” screen but seems to have got stuck in a loop and will not pass this. It reached this screen 5 times before just seeming to stop.

I also put in my old PSU and cables into my new machine and nothing was different. The only two things I am not able to get replacements for are the CPU and motherboard.

[Silent_Scone]

Hi @iSentinels, As you're struggling with lesser capacity modules, can I confirm if you're using a CPU contact frame? Improper socket retention can lead to inconsistent POST behaviour or overclocking issues.

Please note that intial DRAM training can take upward of 15 minutes, especially with larger capacity configurations. Please ensure you're giving the system enough time to complete

[iSentinels]

Hi! I am not using a specific thermal frame (like the am5 Thermalite), but I do have an arctic freezer iii 360 pro. I have reseated the CPU, and when I installed it did the screws alternating to ensure even pressure.

As for dram training, I left the machine training for over two and a half hours last night to check this. It had still not booted when I got back.

[Silent_Scone]

Thanks. Also, I've just realised you don't explicitly say that it works at stock settings - I'm assuming this is both at EXPO and JEDEC (Optimised Defaults)?

First fix attempt - Downgraded to BIOS 3104 via FlashBack, applied some tweaks, system booted successfully into Windows

Can you elaborate on this at all? What tweaks were you able to perform if the system would not complete POST?

Have you tried removing the system from the chassis and seeing if the behaviour persists? 

[iSentinels]

I haven't tried to turn EXPO on yet. I was saving that for when my system was setup and I could start tweaking. So in terms of bios settings, it’s just whatever the defaults are.

As for the initial tweaks, I saw some people online saying the latest bios was causing some people (on reddit) with stable ram configurations on previous bios revisions were having issues on the latest bios. Although 3112(?) said you could not install from this version to a previous revision, another user said they contacted asus and it was fine to flashback to - but it would cause you to lose your settings (I had no settings to revert to). 

I reset the CMOS and flashed the bios back to this revision, and it seemed to work after some initial training. I got windows installed and setup, did a few restarts of my device in this process, and all seemed good. I did asus driver updates and turned pc off overnight. When I came on the next day, I did not manage to get to windows once. I eventually started taking out parts to find the culprit, and could not even get the machine to stay in bios consistently anymore, regularly crashing even when here.

Currently the only parts I have in the machine are:

• AIO Cooler
• 1 Stick (48gb) Ram
• CPU
• Motherboard
• PSU
• 1 HDMI lead into integrated graphics

I do not have it in a case, or anything else plugged in (not even the ssd), and it will no longer consistently go to the bios, if at all.

[Silent_Scone]

If the system is freezing even in the BIOS, I would suspect the board or the CPU; however, it's hard to say which without further testing.

[iSentinels · Accepted solution]

I bought a new motherboard last night (the X870 version of my board), and it seems to have booted and is working now first try. Definitely seems to be something wrong with the board. Will return it. Thanks for the help!

[Silent_Scone]

No worries! At least you're up and running.