u/Due-Pomegranate1372

Problem:

• System can often boot into Windows successfully with all 4 sticks installed
• Windows itself appears stable once booted
• MemTest64 shows no immediate errors
• Main issue is restart / memory training behavior

Question:
Has anyone experienced similar AM5 restart training issues with 4 DDR5 DIMMs? Any stable settings or known fixes for ASUS B850 + Ryzen 9000 + 4 DIMMs?

System:

• ASUS TUF GAMING B850-PLUS WIFI
• Ryzen 7 9800X3D
• 64GB DDR5 (4×16GB Corsair CMK32GX5M2E6000Z36)
• Originally stable with only 2 sticks at DDR5-6000 EXPO
• Added second identical Corsair kit to reach 64GB

Symptoms:

• Restart from Windows frequently hangs with orange DRAM LED
• After failed restart, even cold boot often fails
• Board becomes stuck until CMOS reset
• Sometimes motherboard automatically falls back to safe DDR5-3600 mode after failed training
• After CMOS reset, system can usually boot again

What has been tried so far:

1. BIOS updated to latest available version
2. EXPO disabled
3. Tested multiple memory speeds:
   • 6000
   • 5200
   • 4800
   • motherboard fallback 3600
4. Tried manual voltages:
   • SOC: 1.10V–1.20V
   • DRAM VDD/VDDQ: 1.35V
5. Tried Auto voltages only
6. Tried:
   • Memory Context Restore (MCR) enabled/disabled
   • Power Down Enable enabled/disabled
   • DDR Training Runtime Reduction enabled
7. Cleared CMOS many times
8. Verified original stable kit is installed in A2/B2
9. Cold boot sometimes works after CMOS reset
10. Restart is much less reliable than full shutdown/power-on

Important observations:

• Original 2-stick setup was perfectly stable at 6000 EXPO
• Problems only started after populating all 4 DIMM slots
• Runtime stability seems mostly okay once inside Windows
• Main failure point appears to be DRAM training/retraining during restart/POST
• Failed restart can poison future boots until CMOS reset

Current state:

• Can usually get into Windows at DDR5-4800 after CMOS reset
• Restart still often hangs at orange DRAM LED
• Shutdown/power-on may work more reliably than Restart
• Considering whether this is simply an AM5 4-DIMM limitation with two separate kits, even though they are identical model/spec