Hi ASUS ROG Team,
I’m having stability issues with my new Crosshair X870E Hero when using EXPO I with a 96GB G.SKILL DDR5 kit, and I can’t locate two key memory settings (Command Rate and Gear Down Mode) in the BIOS.
---
System configuration:
- Motherboard: ROG Crosshair X870E Hero (BIOS 1203)
- CPU: AMD Ryzen 9 9950X3D
- Memory: G.SKILL Trident Z5 Royal Neo Gold 96GB (2×48GB) – F5-6000J2836F48GX2-TR5NG (Hynix M-die)
- GPU: NVIDIA RTX 5090 Astral LC
- Cooling: Arctic Liquid Freezer III 420 A-RGB
- OS: Windows 11 Pro (latest build)
---
Problem:
When I enable EXPO I (rated 6000 MT/s CL28-36-36-96 @ 1.35 V), the system boots but becomes unstable when loading large datasets or running memory-intensive workloads. When Steam loads a game, for example.
Windows crashes with memory-related BSODs (MEMORY_MANAGEMENT, PFN_LIST_CORRUPT).
At JEDEC defaults (≈2800 MT/s CL46) the system is completely stable under TM5 DDR5 Ryzen, OCCT RAM, MemTest86, and AIDA64.
Both DIMMs pass individually and are installed in A2/B2.
---
What I’ve tried:
- Latest BIOS 1203 and chipset drivers.
- Tested EXPO I and EXPO II.
- Manually set SoC = 1.25 V – 1.30 V, VDDIO/MC = 1.25 V – 1.30 V, DRAM = 1.40 V.
- UCLK = MCLK (1:1), FCLK 2133 MHz.
- MCR / Power Down disabled.
- Ran TM5 DDR5 Ryzen & OCCT CPU+RAM for stability.
---
Issue:
I cannot find Command Rate (Cmd2T) and Gear Down Mode (GDM) settings anywhere in the BIOS — even under
Advanced Mode → Extreme Tweaker → DRAM Timing Control.
Several other users on Reddit and Overclock.net mention that for 96 GB dual-rank kits, Cmd2T = 2T and GDM = Enabled are required for stability, but these options seem hidden or renamed on X870E Hero BIOS 1203.
---
Request:
1. Could you please confirm the exact BIOS menu path or equivalent setting names for:
- Command Rate (Cmd2T)
- Gear Down Mode (GDM)
- AddrCmdMode / BankGroupSwap (if relevant)
2. Are these parameters hidden when EXPO I is active?
If yes, how can they be manually exposed (for example, by switching Memory Timing Mode → Manual)?
3. If available, could ASUS provide or share a tested memory preset (CMO/OCM) for this G.SKILL kit (F5-6000J2836F48GX2-TR5NG or F5-6000J2836F48GX2-TZ5NR) on Crosshair X870E Hero with Ryzen 9 9950X3D?
---
This memory kit is AMD EXPO-certified for 6000 MT/s CL28, so I’d like to achieve rated performance safely and within spec.
Thank you for your time and for any guidance from the BIOS team!
#X870EHero #ROG #EXPO #DDR5 #BIOS #GSkill
cc: @MasterC @Silent_Scone @Raja-ASUS
