Undervolting with an ASRock B550M ITX mobo BIOS

[ZippyKiYay]

I'm attempting to replicate the settings described in Tech YES City's youtube vid 'How to UNDERVOLT Ryzen 5000 series CPUs (FULL Tutorial).  I've got a Ryzen 5700G on an ASRock B550M ITX motherboard.  The settings I'm looking to change were called the following in an ASUS BIOS:

 

CPU Core Ratio

VDDCR CPU Voltage

VDDCR CPU Offset Voltage

 

In the ASRock BIOS I am unable to find these settings.  Anyone here well versed in the ASRock B550 BIOS?

 

[RONOTHAN##]

I do have some qualms with their undervolt methodology. On Ryzen 5000, you really should be doing voltage offsets or static core settings, instead you should use the Curve Optimizer if you want to undervolt. This will be in the advanced tab, AMD Overclocking, and somewhere in there. -10 all core should work on most CPUs, but keep increasing this until you end up with blue screens at idle (there's unfortunately no way to fully stress test the curve optimizer due to the way it works). 

 

If you really want to do their method of undervolting (I wouldn't recommend it), those setting equivalents will be on the main OC Tweaker menu in the advanced mode of ASRock's BIOS. Core Ratio should just be called CPU Core (Per CCX) or something like that. For the voltages, they should be in the External Voltage Settings submenu and called CPU Core/Cache Voltage (it will ask if you want a fixed of offset voltage respectively). 

[ZippyKiYay]

14 minutes ago, RONOTHAN## said:

If you really want to do their method of undervolting (I wouldn't recommend it), those setting equivalents will be on the main OC Tweaker menu in the advanced mode of ASRock's BIOS. Core Ratio should just be called CPU Core (Per CCX) or something like that. For the voltages, they should be in the External Voltage Settings submenu and called CPU Core/Cache Voltage (it will ask if you want a fixed of offset voltage respectively). 

Per the BIO manual (attached), it shows that 'CPU Core (Per CCX) is a subfolder of 'CPU Frequency and Voltage (VID) Change' in the OC Tweaker section.  However, in my actual BIOS, the 'CPU Core (Per CCX)' folder does not exist.  If I change the value for 'CPU Frequency and Voltage (VID) Change' from "Auto" to "Manual", I do get 2 subfolders: Frequency (MHz) & Voltage (VID).  Also, I should have mentioned that the value he changed for the CPU Core Ratio was from "Auto" to "40.00".

 

For the voltage settings, I was able to locate 2 possible settings under the 'External Voltage Settings' section.  The first is called 'CPU Vcore Voltage' where I can change the value from "Auto" to "Offset Mode".  From there, l can specify a value for 'Offset Voltage (mV)'. The second is called 'VDDCR_SOC Voltage' where I can also set it to "Offset Mode" and then specify a value for 'Offset Voltage (mV)'.  Being that the youtuber changed something called 'VDDCR CPU Offset Voltage', I'm guessing that the second possibility I found is the one to use, right?  Also, the values in the ASUS BIOS for voltage is in Volts and the values in my BIOS are in Mv, so if he set his offset to 0.10V, I'd set mine to 100Mv, right?

ASRock_B550M-ITXac_BIOS_manual.pdf

[RONOTHAN##]

56 minutes ago, ZippyKiYay said:

Per the BIO manual (attached), it shows that 'CPU Core (Per CCX) is a subfolder of 'CPU Frequency and Voltage (VID) Change' in the OC Tweaker section.  However, in my actual BIOS, the 'CPU Core (Per CCX)' folder does not exist.  If I change the value for 'CPU Frequency and Voltage (VID) Change' from "Auto" to "Manual", I do get 2 subfolders: Frequency (MHz) & Voltage (VID).  Also, I should have mentioned that the value he changed for the CPU Core Ratio was from "Auto" to "40.00".

Can you attach a screen shot? Those VID settings are for doing other weird things for tuning, not what you're trying to.  

 

57 minutes ago, ZippyKiYay said:

For the voltage settings, I was able to locate 2 possible settings under the 'External Voltage Settings' section.  The first is called 'CPU Vcore Voltage' where I can change the value from "Auto" to "Offset Mode".  From there, l can specify a value for 'Offset Voltage (mV)'. The second is called 'VDDCR_SOC Voltage' where I can also set it to "Offset Mode" and then specify a value for 'Offset Voltage (mV)'.  Being that the youtuber changed something called 'VDDCR CPU Offset Voltage', I'm guessing that the second possibility I found is the one to use, right?  Also, the values in the ASUS BIOS for voltage is in Volts and the values in my BIOS are in Mv, so if he set his offset to 0.10V, I'd set mine to 100Mv, right?

The VDDCR_SOC voltage and VDDCR CPU voltage are two very different voltages. The SOC voltage is primarily responsible for powering the memory controller and iGPU, while the regular one is what controls the CPU cores. The VCore setting is the equivalent that you're looking for. 

 

 

Again though, his strategy isn't really what you should be using. Use the curve optimizer, it's the intended way to undervolt those CPUs and doesn't have the same issues this static method does. 

[ZippyKiYay]

2 hours ago, RONOTHAN## said:

Can you attach a screen shot? Those VID settings are for doing other weird things for tuning, not what you're trying to.  

First off, thank you RONOTHAN!  I really appreciate your advice and input on this.  Here are screenshots of my 'OC Tweaker' screen & of the section under 'OC Tweaker\External Voltage Settings and Load-Line Calibration'.

231203201711.BMP 231203201754.BMP

[ZippyKiYay]

3 hours ago, RONOTHAN## said:

Again though, his strategy isn't really what you should be using. Use the curve optimizer, it's the intended way to undervolt those CPUs and doesn't have the same issues this static method does. 

I am familiar with Curve Optimizer and am currently using it.  With CO at -10 for all cores, I got a 2.8% increase in the Cinebench multi core score.  However, virtually zero reduction in power usage or temperatures.  Compare that to the results the Tech YES City guy got.... at a 100Mv reduction, power usage dropped by 19% and temps dropped by 13%, while the Cinebench multi core score only dropped by 3.5%.  Then, with his 200Mv reduction (screenshot attached), the power usage dropped by 33% (vs default), the temps dropped by 18% (vs default), and the Cinebench score was only 3.2% lower than it was it the default settings.

 

In addition to running Curve Optimizer, I've also tried disabling 'SoC/Uncore OC MOde' in the 'OC Tweaker' section.  Still, no further reduction in temps or power used, but it did Improve the Cinebench multi core score by another 336 points or 2.4%

[ZippyKiYay]

10 hours ago, ZippyKiYay said:

I am familiar with Curve Optimizer and am currently using it.  With CO at -10 for all cores, I got a 2.8% increase in the Cinebench multi core score.  However, virtually zero reduction in power usage or temperatures. 

CORRECTION -  I've got Curve Optimizer at negative 15.