only C3 C-state

I'm trying to to achieve lower power consumption on 'idle' for my server.

It idles around 18-19 watts having nothing attached. Running RKE2/K8S around 21-22. I've noticed in powertop it only offers c3 state and not like my other machines upto c10.

Asrock riptide B550M P1.40
Ryzen 7 pro 4750G
gskill 64 gb

I've found AMISCE (SCELNX or SCEWIN) to be able to unlock bios and enable the hidden feature for an intel based motherboard. As discribed here:
https://askubuntu.com/questions/1483343/c-states-not-fuctioning-on-ubuntu-server-22-04-please-help#:~:text=So%20you%20have%20to%20enable/change%20hidden%20BIOS%20menus%20by%20using%20AMISCE%20(AMI%20Setup%20Control%20Environment)%20utility%20v5.03%20or%205.05%20for%20Windows%20(it%20can%20easily%20be%20found%20on%20the%20internet).%20So%20you%20have%20to%20install%20Windows%20and%20to%20enable%20Administrator%20password%20in%20your%20BIOS

Amisce (scelnx) errors: AMISCE not supported on this system

So has anybody else solved this problem not having higher c-states for an amd/am4 motherboard ?

I'm happy to wreck the motherboard attempting to achieve this.

I've updated the bios

ubuntu@node02:~$ sudo dmidecode -t bios
# dmidecode 3.3
Getting SMBIOS data from sysfs.
SMBIOS 3.3.0 present.

Handle 0x0000, DMI type 0, 26 bytes
BIOS Information
        Vendor: American Megatrends International, LLC.
        Version: P3.40
        Release Date: 01/18/2024
        Address: 0xF0000
        Runtime Size: 64 kB
        ROM Size: 16 MB
        Characteristics:
               PCI is supported
               BIOS is upgradeable
               BIOS shadowing is allowed
               Boot from CD is supported
               Selectable boot is supported
               BIOS ROM is socketed
               EDD is supported
               Japanese floppy for NEC 9800 1.2 MB is supported (int 13h)
               Japanese floppy for Toshiba 1.2 MB is supported (int 13h)
               5.25"/360 kB floppy services are supported (int 13h)
               5.25"/1.2 MB floppy services are supported (int 13h)
               3.5"/720 kB floppy services are supported (int 13h)
               3.5"/2.88 MB floppy services are supported (int 13h)
               Print screen service is supported (int 5h)
               8042 keyboard services are supported (int 9h)
               Serial services are supported (int 14h)
               Printer services are supported (int 17h)
               CGA/mono video services are supported (int 10h)
               ACPI is supported
               USB legacy is supported
               BIOS boot specification is supported
               Targeted content distribution is supported
               UEFI is supported
        BIOS Revision: 5.17

Enabled c-states under: advanced/amd cbs/cpu common options/global c-state control.

----> Does it needs some other magic setting I missed to enable more than c3 states?

           Pkg(OS) |            Core(OS) |            CPU(OS) 0   CPU(OS) 8
POLL        0.0%    | POLL        0.0%    | POLL        0.0%    0.0 ms 0.0%    0.0 ms
C1          1.1%    | C1          0.9%    | C1          1.0%    0.2 ms 0.8%    0.1 ms
C2        11.7%    | C2        11.2%    | C2        11.1%    0.4 ms 11.2%    0.4 ms
C3        81.8%    | C3        81.5%    | C3        81.3%    3.5 ms 81.8%    3.4 ms

HI ! Thanks for replying and helping to solve the c-states issue!

I've been searching in the bios for the two setttings:

Cool Quiet: enabled
Power Supply Idle Control: Typical

I didn't see them. I've checked advanced/cpu configuration and also went through all the overclocking items. Did I miss them or is it like some b450m forum messages I found that asrock removed these?

Would you know where the two settingss are located in the p3.40 version for b550m ? Most likely I missed them...

no worries!

advanced/cpu configuration/pss support was already on enabled

the article also mentioned disabling
advanced/cpu configuration/smt disabled made not difference (still on pkg(os) c3 max)

all the other mentioned in the reddit post might be already inapplicable of it's version. At least I couldn't find them in my p3.40

On ASRock boards, after updating the BIOS, going to: OC Tweaker > OC Mode , setting it to AMD CBS, and then going to Advanced > AMD CBS > Power Supply Idle Control, and setting it to typical current idle. Press F10, and then Enter to cement it. The UI might be confusing otherwise.