UEFI Settings for ASRock B550 Phantom Gaming-ITX/axchain link icon indicating a link to a heading

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I’ve had a scrap of paper on my desk for about 6 months now that lists the approximate changes I made to the default settings in my motherboard’s firmware. Today, I updated the firmware to version 2.20 and followed these steps again. I decided it’s time to get rid of the paper version and instead put the steps here.

Everyday UEFI Settingslink icon

  1. Exit > Load UEFI BIOS Defaults
  2. Exit > Save Changes and Exit
  3. Boot > CSM > CSM > Disabled
  4. Exit > Save Changes and Exit (the PCIe Above 4G Decoding and Re-Sizable BAR and secure boot are locked out until CSM is disabled)
  5. OC Tweaker > Load XMP Setting > as appropriate for installed RAM (likely not “Disabled”)
  6. Advanced > PCI Configuration > Above 4G Decoding > Enabled
  7. Advanced > PCI Configuration > Re-Size BAR Support > Enabled
  8. Advanced > Onboard Devices Configuration > RGB LED On/Off > Off
  9. Advanced > AMD PBS > PCIe x16 Bus Interface > as appropriate for installed GPU (likely “Gen3” or “Gen4”)
  10. Security > Secure Boot > Secure Boot Mode > Standard > confirm “Yes”
  11. Security > Secure Boot > Secure Boot > Enabled
  12. Boot > Full Screen Logo > Disabled
  13. Exit > Save Changes and Exit

Also, I’ve noticed that if you save any “User Default Profiles,” they can’t be deleted. Even a “Load UEFI BIOS Defaults” or a firmware flash didn’t remove old ones I had there. Possibly a full CMOS clear with the jumper would do it, but I haven’t tested that.

Undervolt the CPUlink icon

Optionally, undervolt the CPU for lower thermal output with Precision Boost Overdrive 2:

Enter the Precision Boost Overdrive menu by choosing AMD Overclocking > Accept > Precision Boost Overdrive. Then, perform the following steps.

  1. Precision Boost Overdrive > Advanced
  2. PBO Limits > Disable
  3. Curve Optimizer > Curve Optimizer > All Cores
  4. Curve Optimizer > All Core Curve Optimizer Sign > Negative
  5. All Core Curve Optimizer Magnitude > as appropriate (30 works for my Ryzen 5 5600X, but see here for further discussion)

Modificationslink icon