Question unreal power limit throttling on dell g7 with an i7-8750h

May 15, 2022
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i have a dell g7 7588 that i purchased back in 7588 and it ran fine for the most part until late 2019, after which it would constantly thermal and power limit throttle. I cleaned the internals and repasted the cpu and then it ran fine for another 6 months after which i had to do the same again as the i7- 8750h would drop down to 0.798 clock speeds and stay there for a solid couple minutes. I kept on repeating the process everytime i faced this problem until last week.

i have repasted and undervolted the cpu and the temps usually range from 47 on idle to 71 when im playing valorant and even then power limit throttling occurs and the cpu speeds suffer and as a result my fps drops to 15 from 160-170. I feel like i have tried and tested every fix or tweak out there but nothing helps and this "gaming" laptop has been reduced to an internet machine.

has anyone else here faced power throttling at such low temps? if so, were u able to fix it?
 
has anyone else here faced power throttling at such low temps
Definitely yes. You are not alone.

This is a common problem with many, many Dell laptops. Dell decided to dream up a new power limit throttling scheme when Intel's 8th Generation CPUs were introduced. This great idea was not that great when these laptops were brand new. Things only got worse as these laptops got older.

What seems to happen is there is an embedded controller (EC) that can send turbo power limits directly to the CPU. These power limits are separate from the MSR and MMIO turbo power limits that ThrottleStop lets you control. The EC seems to be sending a 5 Watt or maybe even a 0 Watt turbo power limit to the CPU. This forces the CPU to run as slow as possible as it tries to get power consumption down to this ridiculously low level. The result is a CPU that randomly gets stuck at 798 MHz for extended periods of time. This of course makes the laptop completely unusable when trying to play any game.

Turn on the ThrottleStop Log File option and you will have a complete record of exactly what is going on. It will confirm this problem. You can copy and paste the data to www.pastebin.com if you want me to have a look.

were u able to fix it?
Now the bad news. There is no fix for this design problem. You can try contacting Dell but as far as I know, Dell is still not willing to admit that this is indeed a serious problem. The cost to properly fix all of the Dell laptops that have this problem would be massive. Your laptop is just the tip of the iceberg.

The only thing that might help make your defective laptop useable is to lower the CPU speed significantly. The severe throttling seems to be triggered by the average CPU temperature. When the average temperature gets up somewhere around 90°C is when these laptops go into severe power limit throttling mode. You can use ThrottleStop to lower the Speed Shift Max value in the TPL window to try and control the CPU speed and heat output. Post some ThrottleStop screenshots and a log file if you need help.
 
@xansarcade
Can you show me a ThrottleStop Log File from a gaming session? Hopefully at least 15 minutes. You can copy and paste the log file data to www.pastebin.com

Does the TS Bench report any errors? An undervolt of -154.3 mV is on the edge of stability for most 8750H. The core and the cache offset do not need to be set to the same value. Some users get better overall results by reducing the amount of cache offset voltage a little and then increasing the core offset voltage to -175 mV or -200 mV. This seems to trick the CPU into using less voltage when running code with a lot of AVX instructions.

Here are some examples that a user sent me. The download includes 3 pictures of some Cinebench testing on an 8750H.
https://drive.google.com/file/d/1B2HZjwlS6B5vO-m6HrkYMuiu8yVh3LvY/view?usp=sharing

Use Cinebench R20 or R23 when testing different voltages. I prefer R20 because it defaults to a single test.

 
May 15, 2022
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@xansarcade
Can you show me a ThrottleStop Log File from a gaming session? Hopefully at least 15 minutes. You can copy and paste the log file data to www.pastebin.com

Does the TS Bench report any errors? An undervolt of -154.3 mV is on the edge of stability for most 8750H. The core and the cache offset do not need to be set to the same value. Some users get better overall results by reducing the amount of cache offset voltage a little and then increasing the core offset voltage to -175 mV or -200 mV. This seems to trick the CPU into using less voltage when running code with a lot of AVX instructions.

Here are some examples that a user sent me. The download includes 3 pictures of some Cinebench testing on an 8750H.
https://drive.google.com/file/d/1B2HZjwlS6B5vO-m6HrkYMuiu8yVh3LvY/view?usp=sharing

Use Cinebench R20 or R23 when testing different voltages. I prefer R20 because it defaults to a single test.


i did the changes right now and here's the logfile with them while playing valorant https://pastebin.com/CgnhHCXM

ts bench starts to report errors around the -170 mark, i went through the log file and temperature is rising to 95 degrees in it. It hasn't even been 2 weeks since i repasted with arctic mx-4, should i use a different thermal compound like the ge lid gc extreme? or is it going to be the same result again. Also this could be a really stupid question but my laptop's battery only lasts for around 30 mins on a full charge so i have unplugged it and i use it on AC power, even though the same things happened when the battery was connected would this ever influence power throttling?
 
May 15, 2022
6
1
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i did the changes right now and here's the logfile with them while playing valorant https://pastebin.com/CgnhHCXM

ts bench starts to report errors around the -170 mark, i went through the log file and temperature is rising to 95 degrees in it. It hasn't even been 2 weeks since i repasted with arctic mx-4, should i use a different thermal compound like the ge lid gc extreme? or is it going to be the same result again. Also this could be a really stupid question but my laptop's battery only lasts for around 30 mins on a full charge so i have unplugged it and i use it on AC power, even though the same things happened when the battery was connected would this ever influence power throttling?
oh and i'll run the cinebench as soon as im done with work. i really appreciate your help here!
 
May 15, 2022
6
1
10
@xansarcade
Can you show me a ThrottleStop Log File from a gaming session? Hopefully at least 15 minutes. You can copy and paste the log file data to www.pastebin.com

Does the TS Bench report any errors? An undervolt of -154.3 mV is on the edge of stability for most 8750H. The core and the cache offset do not need to be set to the same value. Some users get better overall results by reducing the amount of cache offset voltage a little and then increasing the core offset voltage to -175 mV or -200 mV. This seems to trick the CPU into using less voltage when running code with a lot of AVX instructions.

Here are some examples that a user sent me. The download includes 3 pictures of some Cinebench testing on an 8750H.
https://drive.google.com/file/d/1B2HZjwlS6B5vO-m6HrkYMuiu8yVh3LvY/view?usp=sharing

Use Cinebench R20 or R23 when testing different voltages. I prefer R20 because it defaults to a single test.

did a couple runs of r20 and my cpu does not hit anywhere near 3.9 at any point in the test. It usually starts off at 3.4 and throttles down to 2.9 and temps hover between 89-98. For the test i changed the turbo ratio limits to defaults in the hopes that the clocks would go up , but that didnt happen. i am going to get it repasted with gc extreme tomorrow to see if that helps the case. i had used arctic mx4 last week and it only ran fine for like a week after which it started to throttle again.
 
Aug 21, 2022
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Hi @uWebb429 , I actually had my Dell G7 7588 repasted a couple of weeks back. Before repaste the CPU used to throttle down to 800Mhz when it reached 95c degress and and GPU when it touches 77c degrees, after repaste now the GPU seems to be cool around 70c when full load whereas CPU still reaches 95-100c under full turbo boost but it never throttles even at 100c.
(All these noted during gaming)

Was worried since even are underclocking to 3.5 or 3.6Ghz it stil reaches 95c+ which is bad for the CPU to run long at those high temperatures.
So is this normal or should I get it repasted again?
 
Hi @uWebb429 , I actually had my Dell G7 7588 repasted a couple of weeks back. Before repaste the CPU used to throttle down to 800Mhz when it reached 95c degress and and GPU when it touches 77c degrees, after repaste now the GPU seems to be cool around 70c when full load whereas CPU still reaches 95-100c under full turbo boost but it never throttles even at 100c.
(All these noted during gaming)

Was worried since even are underclocking to 3.5 or 3.6Ghz it stil reaches 95c+ which is bad for the CPU to run long at those high temperatures.
So is this normal or should I get it repasted again?
I have a G5 with 9750h and the only way to stop it overheating while gaming is undervolting.
 
Hi @sizzling , I did undervolt with Throttlestop(-150mv core and cache), but it still does reach high temperatures.
It does not throttle, only issue being contant high temperatures of 95-100c
Have you monitored that the undervolt is actually changing the voltage? Some BIOS versions would stop the software controlling the voltage. It might not be throttling but it would be limiting boosting.
 
Aug 21, 2022
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Have you monitored that the undervolt is actually changing the voltage? Some BIOS versions would stop the software controlling the voltage. It might not be throttling but it would be limiting boosting.
Yes I have verified the undervolt through HWmonitor and it is being applied.
Is there any other way to test it?
 
95c+ which is bad for the CPU
Who says 95C is bad? Intel says any temperature under 100C is a safe operating temperature. That is why the vast majority of Intel CPUs produced during the last 14 years have the thermal throttling temperature set to 100C. Some used 105C.

It does not throttle
Trust me, if a CPU core reaches 100C, it will throttle. Some users expect the CPU to drop to 800 MHz and get stuck there until things cool down. That is not how Intel thermal throttling works. The CPU is designed to only slow down the bare minimum to keep the CPU from exceeding 100C. Turn on the ThrottleStop Log File option so you have an accurate record of your CPU temperature and performance while it is thermal throttling. The Afterburner on screen data is not as accurate when a CPU is constantly thermal throttling.

There are lots of thermal pastes that can start to degrade in a week or two when used on a laptop CPU. I would not trust any shop to use a high quality paste. Learn how to do this basic maintenance procedure yourself. Use Noctua NT-H2 or a similar paste.

No need to use HWMonitor. The ThrottleStop FIVR monitoring table shows if the voltages are being applied or not.
 
Aug 21, 2022
6
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Who says 95C is bad? Intel says any temperature under 100C is a safe operating temperature. That is why the vast majority of Intel CPUs produced during the last 14 years have the thermal throttling temperature set to 100C. Some used 105C.


Trust me, if a CPU core reaches 100C, it will throttle. Some users expect the CPU to drop to 800 MHz and get stuck there until things cool down. That is not how Intel thermal throttling works. The CPU is designed to only slow down the bare minimum to keep the CPU from exceeding 100C. Turn on the ThrottleStop Log File option so you have an accurate record of your CPU temperature and performance while it is thermal throttling. The Afterburner on screen data is not as accurate when a CPU is constantly thermal throttling.

There are lots of thermal pastes that can start to degrade in a week or two when used on a laptop CPU. I would not trust any shop to use a high quality paste. Learn how to do this basic maintenance procedure yourself. Use Noctua NT-H2 or a similar paste.

No need to use HWMonitor. The ThrottleStop FIVR monitoring table shows if the voltages are being applied or not.
Hello, so I see in the logfile that it throttles to 3 or 3.4Ghz but comes back to 3.9Ghz later.
No severe throttling observed.
Here's the log file.
https://pastebin.com/p8cPGZ6Z
 
it throttles
Lots and lots of throttling. Everytime you see TEMP in the right column of the log file, that indicates thermal throttling is in progress. There is a mixture of this and lots of PL1 power limit throttling. Your 8750H has a 45W TDP rating but at times it is being limited to less than 20W.

It is bad design by Dell. Your 8750H cannot compete with the same CPU in a properly engineered and properly cooled laptop. There is no fix for Dell's excessive power limit throttling issues.
 
Aug 21, 2022
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Lots and lots of throttling. Everytime you see TEMP in the right column of the log file, that indicates thermal throttling is in progress. There is a mixture of this and lots of PL1 power limit throttling. Your 8750H has a 45W TDP rating but at times it is being limited to less than 20W.

It is bad design by Dell. Your 8750H cannot compete with the same CPU in a properly engineered and properly cooled laptop. There is no fix for Dell's excessive power limit throttling issues.
So I suppose there is no fix for that.
Thanks for the help anyway!
 

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