# Turbo Ratio Limits, TS Bench and HWMonitor readings



## pevik (Nov 8, 2021)

Hi, I'm a little confised about how my cores are (not) affected by turbo ratio limits when looking at HWMonitor readings.

I've got Y-540 with i7-9750H on board.

This is my FIVR setup, please mind Turbo Ratio Limits:






As far as I understand this should lower some core's turbo speed. But then I run TSBench and have a look at HWMonitor readings, I see all cores running 100% with same clock speed:






3393 MHz is way beyond my CPU's normal speed, which means they all got into turbo - but why do they all boost with the same clock? I was expecting to see something like: 4.5 GHz, 4.4 GHz, 3.7GHz, 3.6 GHz, 3.5 GHz and 3.4 GHz.

Do I misunderstood something or is it a problem with my setup?


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## unclewebb (Nov 8, 2021)

pevik said:


> misunderstood


There seems to be a misunderstanding. Adjusting the Turbo Ratio Limits allows you to change the multiplier the CPU uses based on how many cores are active. This setting does not let you change the maximum multiplier for each individual core. That is not possible. That is not how these CPUs work.

You have the 1 Core Active multiplier set to 45. This means that the 45 multiplier will only be used when 1 core is active and the other 5 cores are inactive in one of the low power C states like C3, C6 or C7. It could be any of the six cores that will run at this speed. Whatever core is active runs at full speed. As soon as a second or third core becomes active, the speed of all active cores immediately decreases. At any moment in time, all active cores are locked together and all active cores are forced to use the exact same multiplier. It would be a useful feature if you could run different cores at different speeds but the hardware does not allow this.   

Your FIVR screenshot shows that when 6 cores are active, all 6 cores should be using the 34 multiplier. HWMonitor confirms that. 

For multiplier reporting, ThrottleStop is far more accurate and precise compared to any of the competition. It would be best to ignore other monitoring software. You can trust what ThrottleStop is showing you.


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## pevik (Nov 9, 2021)

Thank you for detailes explanation, I'm glad I asked. I know little regarding how hardware works. I've got some more noobish question, if I may...

When I run TS Bench for 2 threads, it not like 1 or 2 cores are active with 100% performance, rather all of the 6 cores (6 threads also since I disabled hyperthreading for some tests) are active on 50%. Is it also expected behavior? If yes, is there any way I could measure temps with only 1/2/3 cores active?

Also, regarding hardware and the way it works, thanks to ThrottleStop I realized that my fans are not triggered immidiately when CPU gets hot - there is a significant time delay between CPU going hot and triggering fans. When running TS Bench my CPU jumps to 80+ degrees immidiately, and later after ~10 seconds the fans are started to make some significant noise. Why is the delay? Is it ok or is it a sing of something strange?

I'm doing all the research to lower temps of my laptop (my goal is 80 Celcius max under heavy load) while trying to preserve as much performance as I can. I also ordered thermal paste and I'm planning to repaste it before doing some more precise adjustment in ThrottleStop.


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## unclewebb (Nov 9, 2021)

pevik said:


> my goal is 80 Celcius max under heavy load


Why? Intel says that their CPUs can run reliably long term at core temperatures up to 100°C. That is why Intel sets the thermal throttling temperature to 100°C. Under 100°C is safe and over 100°C is not safe. The CPU is designed to automatically throttle and slow down as much as necessary to keep the CPU at a safe temperature. Intel CPUs are well engineered.  

Lower temperatures are good and all that but do not kill yourself trying to reach some unrealistic temperature. Most recent gaming laptops run hot because Intel says it is OK to run their CPUs hot.

Fan speeds are usually not linked to the core temperature sensors. Core temperatures can change instantaneously. If fan speed was based on that, most users would find it to be annoying with the fan constantly spooling up and down. Laptop fans are usually triggered by a different temperature sensor that changes temperature much slower compared to the core temperature. That is why when you go to full load it takes 10 seconds for the fans to finally react. It has proven difficult to come up with the perfect fan algorithm that spools up quickly when needed but is not annoying to end users by constantly over reacting. It sounds like your fan is working normally. 

Windows schedules tasks on any available core. This can happen 60 times every second. It tries to keep the same task on the same core as long as possible but sometimes a different task needs that specific core so the task gets bumped to another core. This happens constantly so a single task might end up spending half of its time on one core and half of its time on a different core. Once again, there is lots of room for improvement in the algorithm that controls this. I think Windows 11 is supposed to be better at this. 

If you want to force a task to run on a specific core, open the Task Manager, go to the Details tab, right click on the task and select the Set affinity menu option. This allows you to tell Windows to only schedule your task on specific cores.  





You can change the Processor Affinity to force the TS Bench to run on whatever core or cores you like but I would avoid doing this to ThrottleStop. Why? If you tell Windows that ThrottleStop is not allowed to run on all cores then ThrottleStop will not be able to access those cores to monitor them. When doing this kind of testing, it would be a good idea to use a different program to load the CPU. That way you can change the Processor Affinity and move that other stress testing program around from core to core without causing any problems for the monitoring portion of ThrottleStop. 

This example shows when ThrottleStop is limited to the last 2 cores (4 threads) of the CPU. 
The monitoring data for the first 8 cores is no longer available because of the Processor Affinity setting. 



 

If your CPU has more than 8 threads, you can double click on the ThrottleStop monitoring table to get an expanded view of all threads.


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