ASRock X99 - FIVR voltages are not unlocking (not adjustable)

Discussion starts here:

Brief problem description:

ASRock X99 hides “FIVR Configuration” for non-overclokcable CPUs. If I unhide it and change voltage offsets for core, cache and system agent, only system agents settings are applied. Core and cache are ignored.

ASUS allows to changes and apply those settings but ASRock doesn’t :frowning:

If I install overclockable CPU then everything works as expected, FIVR Configuration shows up and all voltages are adjustable. So the problem exists only with non-overclockable CPUs.


Is it possible to modify BIOS in such way that voltage settings are applied ?


CPU supports voltage offsets of course. I can change it using Throttlestop.

Setting VarOffset 0xC of SetupCpuFeatures to any value other than 0 will unhide the FIVR Configuration menu.
Let’s see if it also makes settings inside active.

I join the thread with my ASRock x99 Extreme 4

Where exactly this value is?
My FIVR menu unhided by OC Tweaker sub menu Access to USER. Only System Agent works

It is stored in NVRAM.

How to get access to that?

That’s how.

is says offset is out of range

Don’t contaminate my thread please. I will let you know if it works.

What’s your BIOS version? I took the values from latest beta.

Yes, latest beta L4.01

Ah, it’s a different board. I’ll check the values for this one right away…

New VarOffset is 0x9.

I can save 0x01 now with command
setup_var SetupCpuFeatures 0x9 0x01 and read it immediately after that.
But when I reboot with CTRL-ALT-DEL FIVR Configuration is not visible and when I reboot to grub tool the value is back to 0x00

Interesting. It must be some function that sets it to 0 each start if the CPU installed is locked.

I can setup that value and go back to bios without rebooting and FIVR Configuration shows up, but I believe that the code in BIOS that sets the voltage already executed by that time and if I reboot - the value is back to 0x00 and FIVR Configuration is gone.
So I guess we need to figure out how to override that SetupCpuFeatures value before BIOS applies voltages.

I just installed overclockable CPU, and now the value is set to 0x01 as expected after each reboot.
So yes, ASRock queries CPU features upon each boot and setup those values in NVRAM.
It does it for many other CPU features unlike ASUS. For example supported RAM multiplies, it shows only allowed frequencies in BIOS, unlike ASUS that shows everything.

All in all, why need to use FIVR menu? Voltage Configuration menu doesn’t work either?

Voltage configuration is only about 1.8v input voltage from external VRM. All internal CPU voltages are provided by Fully Integrated Voltage Regulator (FIVR), which is inside the CPU. This is how it works on Haswell and Broadwell. Other generation of Intel CPU may work in a different way.

Yes it is possible, I did it for my X99 Taichi quite some time ago so don’t remember how but could look back if interested. Always wondered why people used proof of concept code EFI driver sometimes adapted to FFS for V3 all core turbo exploit. Never occurred to me people were not able to enable the settings in BIOS as proper BIOS mod was always the intended solution.

Did you really figure out how to set core and cache voltage offsets in ASRock bios so that they are applied? I tried pretty much everything since 2020 and eventually switch to ASUS. But I still have ASRock X99 boards.