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ROG Crosshair VIII Hero (Wi-FI) BIOS Stability Settings with BIOS 4805

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Previous Thread :  ROG Crosshair VIII Hero (Wi-FI) BIOS Stability Settings with BIOS 4402 

So, I updated to BIOS 4805 recently and immediately noticed that instability returned after the bios was flashed and I had to work to track down what the cause was.  I found it to be related to the PBO Fmax Enhancer.

System Hardware:

  • ROG Crosshair VIII Hero (Wi-FI) - running BIOS 4805
  • AMD Ryzen 9 5950X
  • CORSAIR Vengeance RGB RT 128GB (4 x 32GB) (PC4 28800) Model CMN128GX4M4Z3600C18
  • ROG Strix RTX 3090
  • Samsung 990 Pro with Custom Heatsink 2TB (boot drive - other drives not listed)
  • CORSAIR AX1600I Power Supply

Steps to mimic my current settings:

  • Enter the BIOS > Exit Menu > Load Optimized Defaults
  • Extreme Tweaker Menu
  • > Overclock Tuner > D.O.C.P. > D.O.C.P. Standard  (This is to get the benefit of the faster memory timings)
  • > Precision Boost Overdrive > PBO Fmax Enhancer > Disabled.
  • > CPU Core Voltage > Offset Mode
  • >> Offset Mode Sign > +
  • >> CPU Core Voltage Offset > 0.12500
  • > DRAM Voltage > 1.36000 (This is because I'm using 4 sticks and it needed a touch more voltage to become stable with D.O.C.P enabled -- refer to your memory!)
  • Advanced Menu > AMD CBS > CPU Common Options
  • >> Global C-State Control > Disabled
  • >> Power Supply Idle Control > Typical Current Idle

Other unrelated BIOS settings I have modified from default:

For Graphic Card Support:

  • Resizable BAR enabled (using the control on the top righthand side of the bios setting menu)
  • - You can verify this setting is enabled within the NVidia control panel.

For Windows 11 Security Support:

  • Advanced Menu > CPU Configuration > SVM Mode > Enabled
  • Advanced Menu > AMD fTPM > Enable Discrete or Firmware TPM -- Your choice which to use
  • Boot > Secure Boot > OS Type > Windows UEFI Mode
  • After boot, check the Windows Security Panel - some items may need to be toggled on and require a reboot.
  • These should enable Core Isolation, Security Processor, Secure Boot, and Data Encryption for Enhanced Security.

Within windows I also run the High Performance Power Setting: Control Panel > Hardware and Sound > Power Options

Once you reach a stable setting, don't forget you can save those BIOS settings using the instructions found here:

I hope this helps others move back towards a stable system and gain the benefits of the latest BIOS update.