First time undervolt and benchmark questions

[jumperwh0]

I have a question about a statement made by unclewebb on another thread: “I like seeing zero throttling during Cinebench.”

I am currently learning about undervolting and will maybe even overclock at some point on the Legion 9 (Intel i9-13980HX). I was able to make it not thermal throttle just with my thermal solutions but it always hits PL1 (125W) on the short test and both PL1 and PL2 (175W) on the long test. I know I can raise power limits but my question is wouldn’t this then cause it to draw more watts and heat up hitting thermal now?

To put it more clearly: How is it possible to not hit any throttling as it’s something I’d like to do, isn’t the nature of Cinebench to push the system to the extreme, and if so, isn’t throttling what brings it back down or finds the top performance?

I’d also like to ask about the safety of setting a high PL1 and PL2, I don’t care about power usage and I figured this can be raised to a higher number than the system can draw (230W according to some sources) meaning it just won’t hit the limit, but isn’t power limit used to also bring thermals down/protect the system? This question comes from the statement I found on other threads about some users just raising it to the max of 4500W on Desktop.

As for undervolting, I’m still testing stability and how different settings affect my system. It’s still using the same wattage as before I applied the settings so thermals are not necessarily improving. Are turbo ratios also the setting I’d use if I want to lower cpu performance = less wattage used?

So far an undervolt of 80.1 mV on cpu core and p cache have increased processing speed by .4 Ghz so if I could slow down the processor a bit now to have better thermals I would take that trade off. Alternatively I would be happy to test overclocking but I would not want to risk thermals as I do heavy work on the unit (and heavy gaming).

Any recommendations you may have for me are very appreciated, my original goal was to simply undervolt but I see there is so much more you can do with Throttlestop.

Thank you!

 

[unclewebb]

I like seeing zero throttling during Cinebench

I do like seeing that but that is no longer possible in most recent laptops with 13900HX or 13980HX processors. Only a few years ago a powerful mobile processor could run Cinebench without exceeding 75 Watts. Now laptops with Intel HX CPUs are reaching 200W or more. It has become impossible to find a laptop that can deal with this kind of power consumption indefinitely. If you run a 13th or 14th Gen HX with unlimited power limits you will likely encounter thermal throttling. If you reduce the power limits you will get power limit throttling and if you reduce the current limits you will get EDP throttling. You can use ThrottleStop to try to balance all of these different types of throttling but it is next to impossible to eliminate all throttling when a HX processor is trying to run at full speed while it is fully loaded.

How is it possible to not hit any throttling

That has now become impossible.

the safety of setting a high PL1 and PL2

No one can guarantee the long term safety of your computer. If safety is important to you, do not use ThrottleStop to increase any of the limits that the manufacturer has set.

turbo ratios

Lowering the turbo ratios in the FIVR window is one way to slow a CPU down. This will reduce maximum performance but should also reduce power consumption.

Undervolting used to be a good way to reduce heat but might not make any difference now. If undervolting allows the CPU to run faster, power consumption and heat will end up being exactly the same.

the max of 4500W on Desktop

The actual max is 4095W. Setting both turbo power limits to this sky high value is equivalent to setting the power limits to Unlimited. You will likely see thermal throttling if you do this but you should not be seeing any power limit throttling.

if I could slow down the processor a bit

I do not know what will work best for you. Some people slow their CPUs down by reducing the turbo ratios or by setting a lower Speed Shift Max value in the TPL window. Others might set lower power limits to control the CPU. If your cooling system can only dissipate 125W of heat, setting the power limits to 125W will help prevent the CPU from thermal throttling. I recommend lowering the turbo time limit. If the cooling system cannot handle 175W sustained for 56 seconds then there is no point in setting the turbo time limit to 56 seconds. Somewhere around 8 seconds at full turbo boost might be all your cooling system can handle.

If you ever find some settings that work well for you then post your results. It is all trial and error.

 

[jumperwh0]

Thank you for the in-depth response. I am still playing around with the tool and testing to see what works best.

I did notice gains in performance which was a surprise as most documentation online state one of the main purposes of undervolting was to reduce temps, but with the increased performance it gives me a window to slow down the cpu in an attempt to get better temperatures. However I’m thinking of going the alternative route and just overclock to get the most out of my system.

My question on power limits came mostly from ignorance on how power draw works on laptops or how electricity truly works overall. I don’t necessarily care about long term safety, I know there are a million factors that can influence how long a system will last (I used to work at Dell support, I know our systems can be used as heaters during winter), rather I don’t understand how the system will balance power draw for all components if the CPU is unlimited, I’m assuming it cannot literally draw unlimited or whatever PL I set, but are other components receiving the same or enough watts if the CPU can ask for whatever it wants?

Thanks!

Update:

So I ran some tests with power limits set very high and the maximum wattage my system achieved was 180W, never crashed so I’m assuming all other components are still getting enough power, I’ll have to research how power draw works to satisfy my ignorance

Of course this made the test be thermal throttling the whole 10 minutes, what I did notice is that average temp was lower than when working with power limits, I’m assuming it’s because wattage is fluctuating instead of locking at PL2 125, but performance worsened.

Is thermal throttling known to be more aggressive than power limits?

If so I guess I should make my ThrottleStop goal to avoid thermal throttling as much as possible

 

[unclewebb]

I should make my ThrottleStop goal to avoid thermal throttling as much as possible

That sounds like a good plan.

Is thermal throttling known to be more aggressive than power limits?

During thermal throttling the CPU is constantly adjusting its speed hundreds of times per second to keep the CPU temperature from exceeding the thermal throttling limit. As far as I know, this rapidly drops the CPU down to 800 MHz, waits a few milliseconds for the CPU to cool and then goes back to full speed again. This happens very rapidly. Many users that are not closely monitoring the CPU speed barely notice the slow down is happening. During games I would think this might cause some slight stuttering but I have never done any testing to prove that theory.

I think power limit throttling only cycles the CPU down to the base frequency. Power limit throttling might be less noticeable compared to thermal throttling.

 

[jumperwh0]

Thank you, I will post results as soon as I’m stable

A quick question I have, I found myself to be stable at -80.1 mV at night, then during the day all the same tests I ran (short, 10m and 30m) crashed, now I’m stable again at same voltage.
Only changes on my FIVR are core and cache at -80.1

I thought it may be temperatures but I’m throttling the same (any time Cinebench R23 starts a new pass). I do live in Miami which can get hotter during the day and relatively colder at night

Does that make any sense? I do my best to reproduce the same initial conditions every time I re-run my testing as to not have too many variables.

Update:

Well, mission aborted. I just remembered that I need to enable and use Hyper-V to use WSL 2 for work and I read that having this virtualization on will make ThrottleStop not function

Was a lot of fun while it lasted, I’ll come back to it in the future on a different unit. Still curious if you could answer my question above, I find it very strange

 

[unclewebb]

If the room temperature varies significantly, it is not unusual for an undervolt setting to go from stable to not stable. I always try to find an undervolt setting that is stable rain or shine. Using the mV Boost feature and setting that to at least 100 can help improve light load stability when undervolting.

WSL 2 for work

WSL2 and using ThrottleStop to adjust voltages are not compatible in Windows 11. That prevents a lot of users from fully using ThrottleStop.

PowerMonkey looks like an interesting project. It allows you to set an undervolt before Windows loads. I have never used this.

GitHub - psyq321/PowerMonkey: UEFI Application for CPU Voltage/Frquency and Power Management adjustment. Great for undervolting.

UEFI Application for CPU Voltage/Frquency and Power Management adjustment. Great for undervolting. - psyq321/PowerMonkey

github.com