Can't change SA voltage on B660+12600KF (MSI Pro B660M-A DDR4)

[VioletGiraffe]

Hi, I have the aforementioned combo of a B660 MSI mobo and unlocked CPU. For some reason it sets the SA voltage to 1.35 V, at least that's what is indicated, and I can't change it. Tried override mode (direct voltage entry), + offset, - offset. Tried disabling XMP, tried changing DRAM voltage from 1.35 to 1.3 thinking they're linked. It won't budge. 1.35 V is a very very high number for Alder Lake, isn't it?

Latest firmware, ofc.

 

Any advice?

 

[Apemanonline]

I have the same board way i did it was using cpu core voltage offset 3rd one from top and set the under voltage there. sa voltage mode auto. Hope this helps.

 

I did this to stop the dam cpu running at 100c every time i did more than open a web page................... (After spending a fortune on new coolers etc )

 

[VioletGiraffe]

Thank you, trying it in a minute! What's your CPU?

[Apemanonline]

12700kf intel 12 series 10000w heater

[VioletGiraffe]

Unfortunately it didn't work, at least the indicated SA voltage didn't change. And I think the vcore offset doesn't work either (which sucks, but it is what I expected from a locked B660 chipset).

[Apemanonline]

dam sorry mate mine is PRO B660M-A DDR4 thats as much as i know. Clever people should be along soon to help.

[VioletGiraffe]

Could you please show the screenshot of your CPU voltage settings? Are you certain that the undervolt actually worked? If it did then I'm doing something wrong.

[unclewebb]

@VioletGiraffe

 

Try running ThrottleStop 9.6

https://www.techpowerup.com/download/techpowerup-throttlestop/

 

Post a screenshot of the FIVR window. Does it show Undervolt Protection at the top middle of the FIVR window?

 

 

Now check the FIVR window to see what microcode version the CPU is using.

 

 

If you have installed the latest BIOS version, you will probably see that Undervolt Protection is enabled. I am not familiar with the MSI B660 motherboard BIOS options. Many of the Asus and Gigabyte B660 boards have a special option in the BIOS so you can use the early 0x104 microcode version. The recent microcode versions have all disabled the ability to undervolt the CPU. You can thank Intel for this decision. Only the early 0x104 microcode allows undervolting. 

[VioletGiraffe]

It looks like none of the options for the core or system agent have any effect. I don't mind most of it as I knew I'm buying a locked board, but why is the SA voltage set to the very high 1.35 V??

 

And another question: if none of the settings work, then why are they present in the UEFI setup?

 

 

[VioletGiraffe]

Will installing an older firmware help?

[Apemanonline]

Bios ver E7D43IMS.1E0

 

Temps stay below 92c and i think i lost a few points in cinebench. Sorry i dont have any knowledge why it worked i just google the how and followed the short post which said adjust offset.

 

Btw im in a different time zone so sorry for late reply only woke up 2 hours ago

[unclewebb]

13 hours ago, VioletGiraffe said:

It looks like none of the options for the core or system agent have any effect.

Your screenshot confirms that the BIOS has enabled Intel Undervolt Protection. 

 

 

Another name for this is IA-CEP or Intel - Current Excursion Protection. If you can find a setting for this or Undervolt Protection in the BIOS, try disabling it. Even if you find this BIOS setting, it might not actually do anything whether it is enabled or disabled. ThrottleStop will not show Undervolt Protection if you can find a way to disable this. 

 

13 hours ago, VioletGiraffe said:

Will installing an older firmware help?

If you can find and install an early BIOS, you might find one that was released before Undervolt Protection existed. Most manufacturers have removed these from their website so you will need to do some Goggle searching. Trying to install an older BIOS version is not without risk. Best case, it will just block you from doing this. Worst case, it could brick your motherboard. 

 

13 hours ago, VioletGiraffe said:

if none of the settings work, then why are they present in the UEFI setup?

Ask your motherboard manufacturer that question. When the B660 boards were first released, they originally allowed CPU voltage control. Intel decided that undervolting was bad so they disabled that feature by releasing a microcode update. The really dumb thing is that you can still use ThrottleStop to increase the CPU voltage. They only disabled lowering the voltage. Increasing the voltage works but of course virtually no one is interested in doing that.

 

Did you try using ThrottleStop to set the System Agent to something other than 1.35V? I know you cannot undervolt the core or the cache while in Windows. I assume that the System Agent is also locked out. Some motherboards may allow you to change the SA voltage in the BIOS before you boot up but you have to be careful. Any undervolting, even a tiny amount, can trigger a huge drop in performance.  

 

3 hours ago, Apemanonline said:

i think i lost a few points in cinebench

Some people lose a lot more than a few Cinebench points when they try to undervolt with Undervolt Protection enabled. Double check your Cinebench scores and compare them to the same CPU when it is running on a motherboard with the Z690 or Z790 chipset. Cinebench scores should be very similar when running a CPU on a B660 board or on a Z series motherboard as long as the CPU is not being overclocked. 

[VioletGiraffe]

4 hours ago, Apemanonline said:

Bios ver E7D43IMS.1E0

Thank you very much! I have not tried the "by PWM" option, hopefully it will work for me as well. And any time is great time for a helpful reply.

 

Meanwhile, I have discovered the answer to my original problem: the SA voltage can be changed! It just requires a power-cycle, simply applying changes and rebooting is not enough. Set it to 1.1 V, and my old kit (2019) of 2x16 GB DDR4 3200 CL18 is still working at 3800 / stock CL 18 timings / 1.3 V. This is amazing, on my previous Zen 1 platform I only managed 3333@1.35 V.