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Undervolt Protection on ASUS with i9 13980HX

Nahte27

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So I've been trying to undervolt the CPU on my ASUS Vivobook Pro 16X with an i9 13980HX. This is an absolute beast of a CPU, but man can it run hot. So I installed XTU and Throttlestop (only using one at a time) to see if there were any undervolt options available, but voltage control was greyed out.

I managed to disable "GFC Lock" and "Overclocking Lock" by setting the variables to 0x0. I also confirmed that the changes stuck even after a full shutdown/restart. This let me adjust voltages, but I could only increase them. Throttlestop had the option to lower voltages, but when applied offset was still +-0.0000. At the top of the Throttlestop FIVR screen it says "Undervolt Protection."

So I took another look at the BIOS flags and saw a variable named "UnderVolt Protection." The description implied that setting it to 0x0 would disable that, so I tried it. However, I still can only raise voltage and not lower it in either XTU or Throttlestop. And the FIVR window still says "Undervolt Protection" at the top.

Does anyone know of another variable that needs to be toggled to allow for undervolting?

I appreciate any advice!

I forgot to mention, I disabled Core Isolation Memory Integrity (HVCI) in Windows as well.
 

Nahte27

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I think I've actually made good progress. Check out this section pulled from the ASUS BIOS.

Form FormId: 0x2887, Title: "OverClocking Performance Menu"
Subtitle Prompt: "OverClocking Performance Menu", Help: "", Flags: 0x0
End
Subtitle Prompt: "", Help: "", Flags: 0x0
End
OneOf Prompt: "OverClocking Feature", Help: "Performance Menu for Processor and Memory.", QuestionFlags: 0x10, QuestionId: 0x3B1, VarStoreId: 0x1, VarOffset: 0x1D9, Flags: 0x10, Size: 8, Min: 0x0, Max: 0x1, Step: 0x0
Default DefaultId: 0x0 Value: 0
OneOfOption Option: "Disabled" Value: 0, MfgDefault
OneOfOption Option: "Enabled" Value: 1
End
SuppressIf
EqIdVal QuestionId: 0x3B1, Value: 0x0
EqIdVal QuestionId: 0x1305, Value: 0x0
Or
End
OneOf Prompt: "UnderVolt Protection", Help: "When UnderVolt Protection is enabled, user will not be able to program under voltage in OS runtime. Recommended to keep it enabled by default. Enabled: Allow BIOS undervolting, but enable UnderVolt Protection in Runtime. Disabled: No UnderVolt Protection in Runtime.", QuestionFlags: 0x10, QuestionId: 0x3B2, VarStoreId: 0x1, VarOffset: 0x381, Flags: 0x10, Size: 8, Min: 0x0, Max: 0x1, Step: 0x0
OneOfOption Option: "Disabled" Value: 0
OneOfOption Option: "Enabled" Value: 1, Default, MfgDefault
End
End

Specifically this bit:

SuppressIf
EqIdVal QuestionId: 0x3B1, Value: 0x0
EqIdVal QuestionId: 0x1305, Value: 0x0
Or
End

It looks to me like the UnderVolt Protection section will be skipped IF QuestionID 0x3B1 OR QuestionId 0x1305 are equal to 0x0.

So I tracked down the QuestionIDs. 0x3B1 is named "OverClocking Feature" which sounds promising. It was disabled by default.

QuestionID 0x1305 is not named. There are a number of Overclocking options that are blocked if this is 0x0. I didn't see anything serious linked, so I enabled it as well.

So now I have QuestionIDs 0x3B1 and 0x1305 enabled which should prevent the suppression of the Undervolt Protection section. However, even though I can still overclock and overvolt, I cannot undervolt, and Throttlestop and HWInfo both show Undervolt Protection is enabled.

I must be missing something...
 
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Asus in their infinite wisdom made it so you could only undervolt in the BIOS and not in Windows...
 
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System Name Asus G16
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Asus in their infinite wisdom made it so you could only undervolt in the BIOS and not in Windows...
MSI seems to be the same way. I have a i7 12800hx processor and I cant even undervolt in the bios. Even though MSI has advanced bios which is like bios used on a desktop computer. I have tried undervolting but it doesn't stick.

So I've been trying to undervolt the CPU on my ASUS Vivobook Pro 16X with an i9 13980HX. This is an absolute beast of a CPU, but man can it run hot. So I installed XTU and Throttlestop (only using one at a time) to see if there were any undervolt options available, but voltage control was greyed out.

I managed to disable "GFC Lock" and "Overclocking Lock" by setting the variables to 0x0. I also confirmed that the changes stuck even after a full shutdown/restart. This let me adjust voltages, but I could only increase them. Throttlestop had the option to lower voltages, but when applied offset was still +-0.0000. At the top of the Throttlestop FIVR screen it says "Undervolt Protection."

So I took another look at the BIOS flags and saw a variable named "UnderVolt Protection." The description implied that setting it to 0x0 would disable that, so I tried it. However, I still can only raise voltage and not lower it in either XTU or Throttlestop. And the FIVR window still says "Undervolt Protection" at the top.

Does anyone know of another variable that needs to be toggled to allow for undervolting?

I appreciate any advice!

I forgot to mention, I disabled Core Isolation Memory Integrity (HVCI) in Windows as well.
I am using a Asus g16, you might be able to undervolt in the bios. On the g16, I have it at .080mv undervolt with the same processor, i9 13980hx.

Try to find "voltage configuration" then hit "p-core voltage offset configuration, hit enabled, in the box p-core voltage offset type in the under you want to undervolt. My max is 80, -.080mv.
 

Nahte27

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I am using a Asus g16, you might be able to undervolt in the bios. On the g16, I have it at .080mv undervolt with the same processor, i9 13980hx.

Try to find "voltage configuration" then hit "p-core voltage offset configuration, hit enabled, in the box p-core voltage offset type in the under you want to undervolt. My max is 80, -.080mv.

Unfortunately this laptop doesn't have anything in the BIOS related to clocks or voltages. The only option ASUS gives me is hyperthreading...

I did find some flags in the BIOS right next to each other that could allow me to undervolt. I found P core offset, E core offset, and +/- toggle for both (make offset undervolt or overvolt). I might set both to - and see if I can achieve even a mild undervolt.
 
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System Name Asus G16
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Unfortunately this laptop doesn't have anything in the BIOS related to clocks or voltages. The only option ASUS gives me is hyperthreading...

I did find some flags in the BIOS right next to each other that could allow me to undervolt. I found P core offset, E core offset, and +/- toggle for both (make offset undervolt or overvolt). I might set both to - and see if I can achieve even a mild undervolt.
The - will be minus undervolt, use that. There night be a limit on the undervolt, my was 80.
 

Nahte27

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The - will be minus undervolt, use that. There night be a limit on the undervolt, my was 80.
The description says the limit is 500 but the hex value listed as the limit is 1000. I tested a very small undervolt (-0.08v) and it didn't totally brick the system so that's something, lol. If I have time today I'll run tests to see if the undervolt was actually applied. Throttlestop and HWInfo didn't show an offset, but if it's set in BIOS it may not show in those apps.

If this works, it's a pain, but we will have a potential way to undervolt ASUS laptops that don't have these options in the BIOS!
 

Nahte27

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So changing the voltage is showing higher min and max voltages in HWInfo and Cinebench scores have dropped. Even though I changed the offset from "+" to "-" I think it's still increasing the voltage. However, I found another flag that looks like it may cause it to skip the +/- check.

Further down the rabbit hole I go...
 

ilford

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The same notebook.

The only thing I can change is the value of AC loadline. I changed it from 170 to 110, the CEP prevented any smaller value by severly degrading the performance. It seems that UVP and CEP cannot be disabled. I also tried the older version 205 hoping it forgets to use the latest microcode to enable the protections but got no luck.
 

Nahte27

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The same notebook.

The only thing I can change is the value of AC loadline. I changed it from 170 to 110, the CEP prevented any smaller value by severly degrading the performance. It seems that UVP and CEP cannot be disabled. I also tried the older version 205 hoping it forgets to use the latest microcode to enable the protections but got no luck.
Interesting. How did you change the AC loadline value? Was it through BIOS flags?
 
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You guys try using windows power options- power saver plan ?
 
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You guys try using windows power options- power saver plan ?
oh dear, windows power plans just plain sucks. For once I prefer the Asus crate software, it controls fan options and power rates.
 

ilford

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Interesting. How did you change the AC loadline value? Was it through BIOS flags?
Yes, by QuestionId 0x275 (offset 0x132).

The benefit is near zero: a single run of Cinebench R23 after a cold boot is scored 30500 and the temperature is as high as before. As I know, an undervolted 13900HX can get 35000+.

I don't know what Asus did, I guess they just ignore those settings and save the best for their game models.
 
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System Name Asus G16
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Display(s) QHD+ 16in 16:10 (2560x1600, WQXGA) 240hz
Power Supply 330w psu
Yes, by QuestionId 0x275 (offset 0x132).

The benefit is near zero: a single run of Cinebench R23 after a cold boot is scored 30500 and the temperature is as high as before. As I know, an undervolted 13900HX can get 35000+.

I don't know what Asus did, I guess they just ignore those settings and save the best for their game models.
There is no way that the 13900hx can get 35000+, on the asus laptop that I use its undervolted by .080, I still get about 31 in r23. The highest that I saw on r23 was about 33k on a MSI gt77 titan.
 
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There is no way that the 13900hx can get 35000+, on the asus laptop that I use its undervolted by .080, I still get about 31 in r23. The highest that I saw on r23 was about 33k on a MSI gt77 titan.
I can get 34.5k single run r23 on my Legion 7i Pro.

32.5k sustained 10 min run.


Both using my 24/7 undervolt of -125mV core and cache.
 

ilford

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There is no way that the 13900hx can get 35000+, on the asus laptop that I use its undervolted by .080, I still get about 31 in r23. The highest that I saw on r23 was about 33k on a MSI gt77 titan.
This is from a Legion Y9000P.
 

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Nahte27

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That's an insane score! It's a shame some performance is left on the table because ASUS has locked down the Vivobook so much. I think the highest I've ever seen on mine is ~30,100 and that's with fans at 100% on a cooling pad.

I'm also not seeing an improvement after changing voltage offset from "+" to "-" and modifying P Core and E Core. There must be some sort of lock, or ASUS just nuked that part of the BIOS. I did notice one of the flags to enable +/- toggle was listed as "undefined" or something like that.
 

ilford

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That's an insane score! It's a shame some performance is left on the table because ASUS has locked down the Vivobook so much. I think the highest I've ever seen on mine is ~30,100 and that's with fans at 100% on a cooling pad.

I'm also not seeing an improvement after changing voltage offset from "+" to "-" and modifying P Core and E Core. There must be some sort of lock, or ASUS just nuked that part of the BIOS. I did notice one of the flags to enable +/- toggle was listed as "undefined" or something like that.
I tried everything, all values are offsets:

UnderVolt Protection (0x381) = 0
Overclocking Mode (0x1D9) = 1
CFG Lock (0x43) = 0
Overclocking Lock (0x10E) = 0
PROTHOT Lock (0x7D) = 0
P-Core Voltage Offset (0x1E0) and Prefix (0x1E2)
E-Core Voltage Offset (0x2B2) and Prefix (0x2B4)
TVB (0x2E3) = 0
EET (0x1D5) = 0
TVBO (0x2E4) = 0
ETVB (0x378) = 0

No one, not a single one contributes. Asus just doesn't allow you to change any value except from their BIOS and they locked it.

As I said, the only thing that can be changed is AC/DC Load line (0x132 0x133 and 0x13C 0x13D), but Asus also disabled "IA CEP Enable (0x334) = 0", so when I set AC Load line to any value lower than 0x6E (110 mo), CEP will be there and the performance is down a lot.

I got a score of 30500 after the change. Not exciting at all.
 

Nahte27

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I tried everything, all values are offsets:

UnderVolt Protection (0x381) = 0
Overclocking Mode (0x1D9) = 1
CFG Lock (0x43) = 0
Overclocking Lock (0x10E) = 0
PROTHOT Lock (0x7D) = 0
P-Core Voltage Offset (0x1E0) and Prefix (0x1E2)
E-Core Voltage Offset (0x2B2) and Prefix (0x2B4)
TVB (0x2E3) = 0
EET (0x1D5) = 0
TVBO (0x2E4) = 0
ETVB (0x378) = 0

No one, not a single one contributes. Asus just doesn't allow you to change any value except from their BIOS and they locked it.

As I said, the only thing that can be changed is AC/DC Load line (0x132 0x133 and 0x13C 0x13D), but Asus also disabled "IA CEP Enable (0x334) = 0", so when I set AC Load line to any value lower than 0x6E (110 mo), CEP will be there and the performance is down a lot.

I got a score of 30500 after the change. Not exciting at all.
Looks like you followed the same path I did. I have almost the exact same changes. However, I did find 2 flags not listed that might be blocking voltage offsets. I'm not great at reading this code, but maybe you will have an idea.

QuestionId 0x3D9 is checked before the mention of P Core offset voltage. I wonder if that means it's suppressing the change if it is equal to 0x1?

SupressIf
EqldVal QuestionId: 0x3D9, Value 0x1

QuestionId 0x1302 is checked before every mention of E Core offset voltage. It goes something like this, incrementing the check by 1 for every cluster:

Cluster 0 Voltage Offset

SupressIf
QuestionRef1 QuestionId: 0x1302
Uint8 Value 0x1
LessThan
End
Cluster 1 Voltage Offset

SupressIf
QuestionRef1 QuestionId: 0x1302
Uint8 Value 0x2
LessThan
End
Cluster 2 Voltage Offset

SupressIf
QuestionRef1 QuestionId: 0x1302
Uint8 Value 0x3
LessThan
End
Cluster 3 Voltage Offset

SupressIf
QuestionRef1 QuestionId: 0x1302
Uint8 Value 0x4
LessThan
End
I don't know if it suppresses the change if the value is less than the question, or the other way around.

Weirdly QuestionId 0x1302 is in VarStoreId 0x2, VarOffset 0x36 in a different store than everything else so far.
 

ilford

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Looks like you followed the same path I did. I have almost the exact same changes. However, I did find 2 flags not listed that might be blocking voltage offsets. I'm not great at reading this code, but maybe you will have an idea.

QuestionId 0x3D9 is checked before the mention of P Core offset voltage. I wonder if that means it's suppressing the change if it is equal to 0x1?



QuestionId 0x1302 is checked before every mention of E Core offset voltage. It goes something like this, incrementing the check by 1 for every cluster:





I don't know if it suppresses the change if the value is less than the question, or the other way around.

Weirdly QuestionId 0x1302 is in VarStoreId 0x2, VarOffset 0x36 in a different store than everything else so far.
The SupressIf directive is used to toggle the visibility of an item in BIOS interface. In an unlocked BIOS, even an item is hidden, its value still affects.

I guess that there is some flag which tells the BIOS code to read the values and send them to the MSR or update the microcode. Currently the values are there but no one reads them. Or, maybe a tool like SmokelessRuntimeEFIPatcher is required to patch the EFI code so we can access the hidden BIOS setting UI.
 

ilford

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I turned off SA GV by setting SaSetup 0x1F1 to 0 and got a minor score improvement to 30605.

Really want to know how to turn off UVP and CEP. :confused:
 

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Nahte27

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I turned off SA GV by setting SaSetup 0x1F1 to 0 and got a minor score improvement to 30605.

Really want to know how to turn off UVP and CEP. :confused:
Same... I wonder if anyone at the Win-Raid forums are willing to tackle this BIOS?

And SAGV is just dynamic memory speeds, right? I wonder if that impacts battery life much.
 

okashiraa

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Looks like you followed the same path I did. I have almost the exact same changes. However, I did find 2 flags not listed that might be blocking voltage offsets. I'm not great at reading this code, but maybe you will have an idea.

QuestionId 0x3D9 is checked before the mention of P Core offset voltage. I wonder if that means it's suppressing the change if it is equal to 0x1?



QuestionId 0x1302 is checked before every mention of E Core offset voltage. It goes something like this, incrementing the check by 1 for every cluster:





I don't know if it suppresses the change if the value is less than the question, or the other way around.

Weirdly QuestionId 0x1302 is in VarStoreId 0x2, VarOffset 0x36 in a different store than everything else so far.
Your bios variables might be write protected like mine were. But I would get error 0x000000008 when trying to write them.

I had to unlock my bios. You can do it with a hex edit method or the UEFI Editor tool github maybe.
Im running an Tongfang laptop (xmg neo 17)with 13900HX and now my best cinebench is 37200 with 186w and -150 undervolt
Before was about 30,000

modding the bios to unlock the menus was the ONLY way i was able to unlock stuffs, incuding the IA current limit, undervolting in windows.... and I tried everything, all the EFI tools, etc.

I turned off SA GV by setting SaSetup 0x1F1 to 0 and got a minor score improvement to 30605.

Really want to know how to turn off UVP and CEP. :confused:
i have CEP enabled but it doesnt effect my undervolt..
Maybe CEP only apples when you use LLC to undervolt
 

ilford

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Your bios variables might be write protected like mine were. But I would get error 0x000000008 when trying to write them.

I had to unlock my bios. You can do it with a hex edit method or the UEFI Editor tool github maybe.
Im running an Tongfang laptop (xmg neo 17)with 13900HX and now my best cinebench is 37200 with 186w and -150 undervolt
Before was about 30,000

modding the bios to unlock the menus was the ONLY way i was able to unlock stuffs, incuding the IA current limit, undervolting in windows.... and I tried everything, all the EFI tools, etc.


i have CEP enabled but it doesnt effect my undervolt..
Maybe CEP only apples when you use LLC to undervolt
The variable storage is not protected: all the values are successfully written (verified with RU and the setup_var tool), but they are just not used.

CEP only affects when you turn down the value of IA AC/DC load line.

The Vivobook is splendid in all other aspects, except this locked BIOS.

Is your notebook stable when you undervolted it by -150mv?
 

okashiraa

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The variable storage is not protected: all the values are successfully written (verified with RU and the setup_var tool), but they are just not used.

CEP only affects when you turn down the value of IA AC/DC load line.

The Vivobook is splendid in all other aspects, except this locked BIOS.

Is your notebook stable when you undervolted it by -150mv?
Yes. I can run cinebench at -190
I used VF curve to raise voltage at low core speeds

The variable storage is not protected: all the values are successfully written (verified with RU and the setup_var tool), but they are just not used.

CEP only affects when you turn down the value of IA AC/DC load line.

The Vivobook is splendid in all other aspects, except this locked BIOS.

Is your notebook stable when you undervolted it by -150mv?
IA CEP has no effect on undervolting. This is a misconception because some older BIOS had misnamed a variable....
I can't find the correct term, but it's some sort of protection that kicks in when the cpu senses voltage thats too low and throws in idle clocks to throttle the cpu. It's unrelated to current.
 
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