Intel Core i9-13980HX Undervolt - Observations and Questions

[janvitos]

Hey everyone!

First of all, thanks to @unclewebb for updating ThrottleStop to 9.5.1 and adding support for 13th Gen Intel CPUs!

I have an ASUS Rog Strix G18 with Intel Core i9-13980HX CPU and am using ThrottleStop to undervolt it.

So far, I'm getting a stable undervolt @ 85 °C average / 92 °C max with a 30 mins Cinebench R23 pass / 1 hour gaming session and the following settings (see screenshots below for additional details):

CPU Core: -139.6 mV
CPU P Cache: -110.4 mV
CPU E Cache: -110.4 mV
Thermal Velocity Boost: NO
PL1: 80 (Clamp)
PL2: 80 (Clamp)
Sync MMIO: YES

So, as I understand from seeing other people push their 13980HX much higher than this, I probably didn't win the silicon lottery. I got a 27300 score in Cinebench with these stable settings. The max I got was 34000, but the CPU got unstable after a few passes. My laptop feels really snappy in general, so I am still happy with the results.

Now, I have a few questions, and I hope some of you might be able to answer them.

1. Unervolting the CPU E Cache seems to have no effect at all. The CPU speed doesn't change and my score in Cinebench stays the same. Is this the intended behavior? Is there no purpose in undervolting the CPU E Cache?

2. A few years ago, when I undervolted CPUs, I would see the temperature dropping. Now, when I undevolt this CPU, I notice the temperature stays the same, but the speed of the CPU (MHz) increases. Is this normal? Is this a new behavior from undervolting? Maybe I missed something?

3. Again, a while back, to find the perfect balance between power and heat, I would undervolt the CPU and adjust the Turbo Ratios until I found the sweet spot. Now, I've done things a bit differently and have been adjusting the CPU's Turbo Power Limits (PL1 & PL2) to find the sweet spot. According to you, what's the better way to proceed? Turbo Ratios or Turbo Power Limits?

4. Would anyone have any other advice or recommendations regarding this undervolt?

Please feel free to post your own 13980HX undervolts

Thanks!

 

[unclewebb]

when I undevolt this CPU, I notice the temperature stays the same, but the speed of the CPU (MHz) increases. Is this normal?

That is normal.

Reducing voltage reduces power consumption which should reduce heat. When your CPU is power limit throttling at 80W, reducing voltage momentarily reduces power consumption. If power consumption drops to 75W, the CPU decides that it can run faster without exceeding the 80W power limit. Power consumption goes back up and you are once again bouncing off the 80W power limit. Faster CPU but power consumption is still exactly the same as what it was before.

Hopefully it makes sense that if power consumption has not changed then the CPU temperature will be exactly the same.

The temperature will only drop when undervolting if your CPU is not bouncing off a power limit. If you undervolt and power drops from 60W to 50W, then you should see a cooler running CPU.

Turbo Ratios or Turbo Power Limits?

I have never tested a 13th Gen laptop or any recent laptop for that matter so use whatever settings work best for you. I prefer leaving the turbo ratios at their default values and then adjusting the turbo power limits to what the cooling can manage. This may or may not be the best way to control your new laptop. This method of CPU control was never based on any hands on testing. I just thought it would be easier that if your cooling was good for 80W then setting PL1 to 75W or 80W would make sense so that your CPU does not need to thermal throttle very often. Setting PL2 10% or 20% higher than PL1 also makes some sense. If your laptop cooling system can only handle the increased PL2 power for 8 seconds then lower your turbo time limit to 8 seconds.

find the perfect balance

There is no perfect balance. Different games and different apps work parts of the CPU and GPU differently. No point in going OCD trying to get the last MHz and last degree out of a laptop. Come up with some general settings that you do not have to constantly adjust every time the sun comes out from behind the clouds. That is what I like. Just some simple settings that improve things that do not need to be constantly micro managed. Modern laptops are quite powerful. No need to live life right on the edge of stability to get 100 more Cinebench points.

 

[janvitos]

Thanks for your input @unclewebb! Nice to see we're on the same page.

Do you have any more wisdom to share about the CPU E Cache undervolt not having any effect on CPU speed or temps? CPU E Cache is new to me, so I'm really stumped about this one.

 

[janvitos]

Ok, I discovered something really important and interesting about this CPU. It hates to be power restricted!

I was able to get a much better undervolt by tuning the Turbo Ratios rather than the Turbo Power Limits.

I will update my main post a bit later with my findings.

 

[unclewebb]

CPU E Cache undervolt

If the E cache is not a significant source of power consumption, undervolting it will not result in a significant decrease in power consumption. The CPU speed and temps might not change any meaningful or noticeable amount. The cores are always going to be the main source of power consumption. Undervolting the core will always be the most productive thing you can do.

My belief has always been, do not make any changes in ThrottleStop unless you can prove that it provides an increase in performance or a decrease in temperatures. Too many people like to make random changes based on a YouTube video they saw and then do not back up their changes with any testing.

Keep testing. That is always best.

 

[janvitos]

My belief has always been, do not make any changes in ThrottleStop unless you can prove that it provides an increase in performance or a decrease in temperatures.

This is exactly how I view it as well. I don't want to make any changes that won't make things faster or more stable. So with this in mind, I will not make any changes to the E Cache.

Once again, I am thrilled with the results I've obtained by tweaking the Turbo Ratios and leaving the Turbo Power Limits at their default levels.

I've now managed to get a stable undervolt that performs close to my previous unstable undervolt, with much lower temperatures.

My findings are coming soon...

 

[janvitos]

So, after doing lots of testing with my i9-13980HX CPU, I got some really interesting and conclusive results that helped me achieve a much better, cooler and more stable undervolt.

Instead of trying to find the Turbo Power Limits that would achieve best performance and lowest heat, which resulted in unstable undervolts and lots of heat, I decided to leave the TPLs at their default values and started undervolting the Core and Cache.

These are the default Turbo Power Limits in effect:

MSR: 175 / 175
MMIO: 110 / 120

These are the voltages I set for a stable undervolt:

CPU Core Offset Voltage: -150.4 mV
CPU P Cache Offset Voltage: -120.1 mV
CPU E Cache Offset Voltage: 0 mV

For some reason, changing the CPU E Cache had absolutely no effect on the CPU's speed or temperature. If anyone got different results, I would be really happy to hear about them.

After getting this undervolt stable, I still wasn't happy with the heat spikes I kept getting on some Cores. The spikes ranged from 97 °C to sometimes 100 °C!

So, I decided to start lowering the Performance Cores Turbo Ratios from their default values of 56 (Group 0 and 1) / 52 (Groups 2 to 7) to a fixed number for all Groups. I started with 50, but there were still some heat spikes, so I ended up with a lower number.

This is the Turbo Ratio I ended up using:

Turbo Ratio (All Groups): 47

With this undervolt and Turbo Ratio, I got a stable gaming laptop that scores 31600 in Cinebench R23, 13880 in 3DMark TimeSpy, averages 70 °C while gaming and only spikes up to 89 °C.

Now, I am finally satisfied and truly happy about this undervolt

I might try to push the voltages lower, but I doubt a few millivolts will have any considerable impact on performance or temperature.

If you heave any questions, feel free to ask!

 

[Elvira]

@janvitos Thanx for this thread, I was thinking to create one for this CPU. Should have one dedicated thread for each CPU so it's more easy to diagnose and exchange experiences.
I have the same laptop ASUS Rog Strix G18 as you. I always start monitoring on a Windows backup up with default settings on XTU and I got some power limit even with the factory default PL1+PL2 at 175w. They started to stop when I increased the PL1 and PL2 to 180w. But still got one PL on benchmarks. So that's why on screenshoots I set them to 185w. I got the bug too on XTU when you start to apply the settings, the watchdog drivers is greyout in settings when your reboot and all settings are gone. That's why I love Throttlestop.

I reduced clock speed for P-Cores and E-cores for gaming and to get very nice temps and I am not loosing a lot of perfomance in games. I stand on those undervolts for now. Everything look like stable.
Greetings. (I watched "GizmoSlipTech" undervolt video on youtube that helped me a lot too)

PS : @unclewebb thanx again for this piece of gold.

 

[janvitos]

I just wanted to post a little update and say that I ended up returning the ASUS Rog Strix G18 laptop.

I wasn't happy with the power the i9-13980HX was delivering or the performance of the RTX 4070.

The CPU could barely handle 80-90 W of constant power and would heat up really bad, regardless of the undervolt. This CPU is sold as a 175 W capable processor, and I was getting nowhere near that, not even in short bursts.

I read many reviews online (including this one https://www.ultrabookreview.com/61998-asus-rog-scar18-review/) saying the CPU should be capable of 100-140 W stable power with 85-90 °C temperatures on stock voltage. My experience was not remotely close to this.

I suspect the laptop I had bought probably had a really bad CPU or the heatsink was warped and not cooling properly.

At first, I wanted to try a second laptop to see if it would provide better CPU power and cooling, but I decided to get my money back and stick with my old Legion Y740-17IRHg laptop, which is still a good gaming machine.

I will probably wait for another generation of CPU and GPU before upgrading.

Cheers!

 

[metallidevils]

Hi all,

I have the same laptop, with what I believe is the newest bios version (313 - I can offset to -80mv in the bios).

I installed the latest throttlestop. When I set the voltage offset in the FIVR tab, the top right corner of the fivr screen's 'offset' column does not reflect this; it still shows 0. Is there some other setting in the bios that I need to unlock - @unclewebb @janvitos ?

edit: I also saw from a reddit post that I need to disable virtualization under the core isolation settings, I did that as well but still don't see the offsets applied.

edit2: even though I disabled the virtualization in the UI, it still seems to be enabled under system information.

final edit: I had to use the 'windows features' method here: https://www.anoopcnair.com/disable-virtualization-based-security-windows/ and now it is working - thanks!

 

[metallidevils]

I think I lost the silicon lottery because I can't get better than a -135 on core.

I did get an 18,845 timespy:

Graphics Score 19,180
CPU Score 17,148

and the CPU barely touches 90 degrees, so I think overall I'm in pretty good shape.

 

[unclewebb]

Has anyone tried using this feature on their HX processors?

This allows a person to increase the voltage at the low end of the voltage curve. Adding 100 mV to the low end might allow you to offset undervolt further for better full load temperatures or performance. This feature might help reduce any light load stability issues.

I do not own a HX processor so I have never had a chance to test this theory out. Do some Cinebench testing to see if there is any real world improvement.

 

[metallidevils]

Has anyone tried using this feature on their HX processors?

View attachment 304186

This allows a person to increase the voltage at the low end of the voltage curve. Adding 100 mV to the low end might allow you to offset undervolt further for better full load temperatures or performance. This feature might help reduce any light load stability issues.

I do not own a HX processor so I have never had a chance to test this theory out. Do some Cinebench testing to see if there is any real world improvement.

I'm excited to try this out! In HWInfo I see my minimum clock speeds at 798 mhz, not 800mhz. Would this be liable to cause an issue if the clock speed went below 800? if I understand this feature correctly, going below 800 mhz would be liable to cause a BSOD.

If I set this value to 100, should I try subtracting 100 from my current core voltage value (which is -135)? Or is that too extreme? Should I aim for a number where the mvBoost is equal to whatever additional offset I apply, so at lower clock speeds I still have the same effective offset?

 

[unclewebb]

minimum clock speeds at 798 mhz, not 800mhz

It is the same thing. 800 MHz is just the rounded value of 798 MHz.

Would this be liable to cause an issue if the clock speed went below 800?

No issues. The minimum clock speed is approximately 800 MHz or 798 MHz if you want to be more precise. The CPU does not go below this value.

going below 800 mhz would be liable to cause a BSOD

No. Your HX CPU does not go any meaningful amount under 800 MHz.

If I set this value to 100, should I try subtracting 100 from my current core voltage value

Go in small steps. Try using an offset undervolt of -150 mV. Does the extra voltage at 800 MHz feature allow you to use a larger offset undervolt reliably? It might. This has never been tested on HX CPUs so you are the official guinea pig.

Why did you originally decide to stop at -135 mV? Was your computer crashing when it was fully loaded or were you having problems with your computer crashing when it was lightly loaded? The 800 MHz voltage boost feature is to try and solve any crashes that happen when lightly loaded. It will not fix voltage related crashes that are happening when you undervolt too much and the CPU is fully loaded.

 

[metallidevils]

It is the same thing. 800 MHz is just the rounded value of 798 MHz.


No issues. The minimum clock speed is approximately 800 MHz or 798 MHz if you want to be more precise. The CPU does not go below this value.


No. Your HX CPU does not go any meaningful amount under 800 MHz.


Go in small steps. Try using an offset undervolt of -150 mV. Does the extra voltage at 800 MHz feature allow you to use a larger offset undervolt reliably? It might. This has never been tested on HX CPUs so you are the official guinea pig.

Why did you originally decide to stop at -135 mV? Was your computer crashing when it was fully loaded or were you having problems with your computer crashing when it was lightly loaded? The 800 MHz voltage boost feature is to try and solve any crashes that happen when lightly loaded. It will not fix voltage related crashes that are happening when fully loaded.

Thanks for the explanation. It seemed to happen at light loads so in theory this solution is perfect for me. Going to give it a try!

 

[unclewebb]

It seemed to happen at light loads

That is what I noticed during testing and from user feedback. Light load instability when undervolting too much is much more common than full load stability problems.

The regular H series CPUs do not support this new ThrottleStop feature. This could be a very useful feature for the HX processors. Imagine being able to reliably run a -180 mV offset undervolt with no worries about light load stability. That would be wonderful.

 

[metallidevils]

Hm, so it didn't work, I still got a BSOD - happened when I opened cinebench

More concerningly, I can't seem to get that field to 'unstick'. I unchecked it in throttlestop, but HWInfo seems to remember it. Under 'IA Overclocking' in HWInfo, I see a positive voltage offset, not my undervolt, even if I disable the checkbox - and this even persisted on a restart.

edit: looks like I had to keep the checkbox enabled, set it to 0, save, and then I could uncheck it and save again and I see my undervolt applied in HWInfo.

When I BSOD, it seems like it usually happens when it's coming 'down' from a CPU intensive task, like after cinebench completes. I have a feeling something like the 800mhz boost is a step in the direction of what I need, but my uneducated guess is that I'd need it to kick in at a speed higher than 800.

 

[unclewebb]

When I BSOD, it seems like it usually happens when it's coming 'down' from a CPU intensive task

My 10th Gen 10850K had this issue. The wild voltage swings from full load to idle were excessive and caused instability. My fix was to reduce the load line calibration settings. It totally fixed this annoying issue. A laptop BIOS probably does not give you access to the LLC settings.

Thanks for sharing your test results. Did you only try setting the 800 MHz boost feature to 100 mV? You could try +200 mV. On my 10850K, this increases the entire low end of the voltage curve. It probably still won't help you with your issue which seems more load line related. Something to play with if you are feeling lucky.

 

[metallidevils]

My 10th Gen 10850K had this issue. The wild voltage swings from full load to idle were excessive and caused instability. My fix was to reduce the load line calibration settings. It totally fixed this annoying issue. A laptop BIOS probably does not give you access to the LLC settings.

Thanks for sharing your test results. Did you only try setting the 800 MHz boost feature to 100 mV? You could try +200 mV. On my 10850K, this increases the entire low end of the voltage curve. It probably still won't help you with your issue which seems more load line related. Something to play with if you are feeling lucky.

Appreciate all of your assistance. It definitely seems like it's due to the swings, in both directions. On more than one occasion, it'd BSOD within a few seconds after completing cinebench, and then on other occasions, it would blue screen or cause cinebench to not even open at all. I didn't realize that the setting increased the entire low end of the curve. I'll have to look for some sort of voltage curve visualizer.

 

[unclewebb]

I didn't realize that the setting increased the entire low end of the curve.

That is how my 10850K works. No one has shown me any testing of a 13th Gen HX CPU.

I adjust the Speed Shift Min and Max values in the TPL window to the same value. This trick allows me to run the CPU at any speed I like when testing. Do this with the CPU idle and watch the VID voltage that is reported at different CPU speeds. It might give you some idea about how the Boost feature changes the VID voltage at different points along the voltage curve.

 

[metallidevils]

@janvitos Thanx for this thread, I was thinking to create one for this CPU. Should have one dedicated thread for each CPU so it's more easy to diagnose and exchange experiences.
I have the same laptop ASUS Rog Strix G18 as you. I always start monitoring on a Windows backup up with default settings on XTU and I got some power limit even with the factory default PL1+PL2 at 175w. They started to stop when I increased the PL1 and PL2 to 180w. But still got one PL on benchmarks. So that's why on screenshoots I set them to 185w. I got the bug too on XTU when you start to apply the settings, the watchdog drivers is greyout in settings when your reboot and all settings are gone. That's why I love Throttlestop.

I reduced clock speed for P-Cores and E-cores for gaming and to get very nice temps and I am not loosing a lot of perfomance in games. I stand on those undervolts for now. Everything look like stable.
Greetings. (I watched "GizmoSlipTech" undervolt video on youtube that helped me a lot too)

PS : @unclewebb thanx again for this piece of gold.

Are you still able to stay at UV values this aggressive? I find that every few days I've had to dial back a few mv, I've gotten around one BSOD every 3-4 days, always when the CPU is basically idle. I think the mv Boost at 800 is exactly what I need in theory, but I still saw BSODs with that, and it didn't seem to report properly in HWinfo even after unchecking it, so I was a bit spooked by that feature,

My 10th Gen 10850K had this issue. The wild voltage swings from full load to idle were excessive and caused instability. My fix was to reduce the load line calibration settings. It totally fixed this annoying issue. A laptop BIOS probably does not give you access to the LLC settings.

Thanks for sharing your test results. Did you only try setting the 800 MHz boost feature to 100 mV? You could try +200 mV. On my 10850K, this increases the entire low end of the voltage curve. It probably still won't help you with your issue which seems more load line related. Something to play with if you are feeling lucky.

If I set the 800 mhz boost to 200 mv, and my actual core undervolt was less than 200 mv, then this would actually increase my idle voltage over stock, right?

Is there any way to visualize the 'curve' that this boost value generates?

 

[unclewebb]

it didn't seem to report properly in HWinfo even after unchecking it

It is up to you to reset the mV Boost voltage if that is what you want. With mV Boost still checked, set it to 0, press Apply and then clear the mV Boost box before pressing OK. If you clear the mV Boost box and immediately press OK without first resetting it, the mV Boost voltage value will be left as is. The mV Boost value will continue to be applied to the CPU if you do not first reset it.

then this would actually increase my idle voltage over stock, right?

Yes. If you boost more than you undervolt, the voltage at 800 MHz should be higher compared to what the default voltage would be.

visualize the 'curve'

It is pretty simple. This feature raises up one voltage point at the lower end of the curve. If you raise this one point up significantly, all of the other points that need to be raised will be raised automatically. As the MHz increase and you go up the voltage curve, each point will be equal to or higher than the previous point.

If you did something crazy like set the mV Boost to +499 mV, it might automatically raise the first 4 or 5 voltage values just to make sure that the voltage is always equal to or greater then the previous point as you go up the curve.

With some 13th Gen HX processors, the real problem might be the default load line calibration settings. This can cause wild voltage swings when going between idle and full load and back to idle again. I do not know if the ThrottleStop mV Boost feature will be able to fix this stability problem.

 

[metallidevils]

It is up to you to reset the mV Boost voltage if that is what you want. With mV Boost still checked, set it to 0, press Apply and then clear the mV Boost box before pressing OK. If you clear the mV Boost box and immediately press OK without first resetting it, the mV Boost voltage value will be left as is. The mV Boost value will continue to be applied to the CPU if you do not first reset it.


Yes. If you boost more than you undervolt, the voltage at 800 MHz should be higher compared to what the default voltage would be.


It is pretty simple. This feature raises up one voltage point at the lower end of the curve. If you raise this one point up significantly, all of the other points that need to be raised will be raised automatically. As the MHz increase and you go up the voltage curve, each point will be equal to or higher than the previous point.

If you did something crazy like set the mV Boost to +499 mV, it might automatically raise the first 4 or 5 voltage values just to make sure that the voltage is always equal to or greater then the previous point as you go up the curve.

View attachment 305809

With some 13th Gen HX processors, the real problem might be the default load line calibration settings. This can cause wild voltage swings when going between idle and full load and back to idle again. I do not know if the ThrottleStop mV Boost feature will be able to fix this stability problem.

From my testing of the mv boost feature, here were my findings.

I set the core offset to -150 mv. I set the mv boost to 50mv.

My expectation (please correct me if I am wrong) is that at idle, HwInfo should report my core offset to be -100mv. In actuality, it was showing +50.

My next expectation would be that upon a restart, and without running Throttlestop, HwInfo would show stock voltages. In actuality it still showed +50.

It wasn't until I set this value back to 0 and saved in throttlestop, that HwInfo went back to showing my core undervolt.

 

[unclewebb]

@metallidevils

You need to lock your CPU to 800 MHz when testing. Are you doing that? Try setting Speed Shift Min and Speed Shift Max to 8 and see if your CPU is steady at 800 MHz. This trick used to work for me on previous CPU Gens. You need to do this so the VID data you are looking at is consistent.

I have not used HWiNFO to see what it reports. Try using the VID voltage that ThrottleStop reports on its main screen.

Here is what I get when mV Boost is set to 100. The VID voltage at 800 MHz went up +90 mV.

My expectation

Your expectations sound reasonable but I have never tested this feature on a 13th Gen CPU so I have no idea what to expect.

upon a restart

Some computers do a fast restart. They might not be properly resetting all of the voltage registers like they should be doing. Hold the Shift key down on the keyboard when you request a restart. This forces Windows to do a full restart and not a fast restart. That might reset the register that contains the mV Boost offset voltage data.

 

[Darthsanzodius]

Hi Gents was just wondering if it's safe to just do this when I'm gaming. I'm just ticking the disable turbo during GAMING on Asus Strix G18. Sorry i'm a newbie on this. Thank you. BTW just grabbed one of the screens from previous post thanks.