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Undervolting Dell Latitude 7490 with I7-8650U

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System Name Dell Latitude 7490
Processor I7-8650U
Motherboard 0KP0FT
Memory 16GB RAM
Video Card(s) Intel UHD Graphics 620
I've been messing around with ThrottleStop for few months figuring out to maximize my cpu's performances. All I know for that my cpu temp is high when gaming (is it because my room is too hot? I think my room is like 29C). So I need some advices if people can help me with these settings

1597073385512.png



1597073426976.png



1597073469054.png


Settings for my CPU and GPU :

CPU Core & Cache : -133.8 mV (Currently stable for now)
GPU & iGPU Unslice : 120.1 mV (Also stable)

And I also underclocked my cpu when some cores are used

1 cores active - 4.2 GHz
2 cores active - 3.9 GHz
3 cores active - 3.6 GHz
4 cores active - 3.4 GHz

By the way, should I put 7.5w or 15w for the Type-C Connector Power in the BIOS?

CPU Core & Cache : -133.8 mV (Currently stable for now)
GPU & iGPU Unslice : 120.1 mV (Also stable)

Turns out my game kept crashing so I changed it to -130.9 mV and -117.2 mV
 
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Try increasing the turbo boost power limits, then increasing the undervolt again.
 

unclewebb

ThrottleStop & RealTemp Author
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Is that screenshot when idle? Looks like something is running in the background, creating heat. An idle CPU should be around 0.5% or less in the C0 state and 99% in C7.

High room temps will cause high computer temps.
 
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Is that screenshot when idle? Looks like something is running in the background, creating heat. An idle CPU should be around 0.5% or less in the C0 state and 99% in C7.

High room temps will cause high computer temps.

I guess not? Because I only had chrome open. Any suggestions?
 
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What do you see with Chrome closed?

This is when idle, my cpu utilization is mostly 3% and it rises up to 8% or 9% when my cursor is moving

1597105610526.png


I was moving my cursor around and it seems like the C7 dropped to 70<, it that normal?
 

unclewebb

ThrottleStop & RealTemp Author
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There are some poorly written laptop mouse pad drivers that sample the mouse pad billions of times per second. Totally unnecessary. Try using an external USB mouse and see if this goes away. You might have a driver problem.
 
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There are some poorly written laptop mouse pad drivers that sample the mouse pad billions of times per second. Totally unnecessary. Try using an external USB mouse and see if this goes away. You might have a driver problem.

Oh I forgot to tell you that I'm using a 2.4 GHz wireless mouse

Try increasing the turbo boost power limits, then increasing the undervolt again.

It doesn't work instead it just keeps giving me BSODs
 
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There are some poorly written laptop mouse pad drivers that sample the mouse pad billions of times per second. Totally unnecessary. Try using an external USB mouse and see if this goes away. You might have a driver problem.

Is there anything I can do at this point?
 

unclewebb

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I thought it might be a track pad driver to blame. Is your mouse using the default Windows driver or its own driver? My CPU spends an extra 2% of its time in the C0 state when I move the mouse around. Poorly written drivers will use more CPU cycles.

With only Google Chrome and ThrottleStop open on the desktop, this is what I see when idle.



The cores spending 99% of their time in C7 is normal. A CPU that only needs to spend 0.5% or less of its time in the C0 state is also normal. The screenshot you posted is nothing like that. You must have some excess stuff running in the background that is creating unnecessary heat. Have a good look in the Task Manager under the Details tab. If you see something running that does not need to be running, try disabling it and see if you can improve your C state numbers.

Under the Performance tab you can also try using the Resource Monitor. This might show you what apps are behaving badly.
 
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I thought it might be a track pad driver to blame. Is your mouse using the default Windows driver or its own driver? My CPU spends an extra 2% of its time in the C0 state when I move the mouse around. Poorly written drivers will use more CPU cycles.

With only Google Chrome and ThrottleStop open on the desktop, this is what I see when idle.



The cores spending 99% of their time in C7 is normal. A CPU that only needs to spend 0.5% or less of its time in the C0 state is also normal. The screenshot you posted is nothing like that. You must have some excess stuff running in the background that is creating unnecessary heat. Have a good look in the Task Manager under the Details tab. If you see something running that does not need to be running, try disabling it and see if you can improve your C state numbers.

Under the Performance tab you can also try using the Resource Monitor. This might show you what apps are behaving badly.

The trackpad is based on Dell's driver and most of my drivers are from Dell. The driver is also the latest one for this laptop.

1597282065571.png


It seems like there's nothing suspicious here and mostly are from the systems.
Probably there's something wrong with one of drivers?
 
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After few days of researching I found out that c states are just fine like at least 2.6 in C0% and the screenshot what makes the c states look a bit different comparing with those pics above. Also, I tried cleaning the fan and opened the heatsink and it looks like the thermal paste is dry.? I guess it makes sense why my laptop is running hot. My question is : should I replace the thermal paste? (ive never really replace any thermal paste though)
 

unclewebb

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If you removed the heatsink and the thermal paste is dry, you have to clean both surfaces and apply new thermal paste. Even if the thermal paste looked beautiful, anytime you disassemble, you have to clean the CPU and heatsink and replace the thermal paste before reassembling.
 
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If you removed the heatsink and the thermal paste is dry, you have to clean both surfaces and apply new thermal paste. Even if the thermal paste looked beautiful, anytime you disassemble, you have to clean the CPU and heatsink and replace the thermal paste before reassembling.

So I've made a mistake when opening the heatsink cause I was only trying to clean the fan. I don't know much about those but after putting all back together, the temperature doesn't change. Also theres a tape connected with the fan and the heatsink so I removed both fan and the heatsink and pretty much clean the fan. Should I remove the tape?
 
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A picture would help.
 
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So I've made a mistake when opening the heatsink cause I was only trying to clean the fan. I don't know much about those but after putting all back together, the temperature doesn't change. Also theres a tape connected with the fan and the heatsink so I removed both fan and the heatsink and pretty much clean the fan. Should I remove the tape?
You mean the heat pipe?
Some laptops you have to remove the heatsink to get the fan out, that just means you should replace the thermal paste when replacing the heatsink.
 
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You mean the heat pipe?
Some laptops you have to remove the heatsink to get the fan out, that just means you should replace the thermal paste when replacing the heatsink.

yeah. this one just connects both of the fan and heatsink with tape. theres one time where i attempted remove the tape a bit and now im worried that it'll affect the heat so now the tape is not sticky.? right now im a bit worried if i should replace the tape or just remove it. i dont even know whats the function of the tape
 
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So I've replaced the thermal paste today with silver mx-4 and it seems like the temp is getting hotter unlike the previous thermal paste which probably the stock one. Is that normal?
 
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No. Try again. Spread a very thin and even layer. Than tighten the screws according to the numbers on them. Do as many attempts as needed until reaching temp readings on all cores with a difference less then 7-8 degrees Celsius. I would choose a better paste with higher max working temp.
 
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No. Try again. Spread a very thin and even layer. Than tighten the screws according to the numbers on them. Do as many attempts as needed until reaching temp readings on all cores with a difference less then 7-8 degrees Celsius. I would choose a better paste with higher max working temp.

I'll try my best.
 
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I've been messing around with ThrottleStop for few months figuring out to maximize my cpu's performances. All I know for that my cpu temp is high when gaming (is it because my room is too hot? I think my room is like 29C). So I need some advices if people can help me with these settings

View attachment 165186


View attachment 165189


View attachment 165190

Settings for my CPU and GPU :

CPU Core & Cache : -133.8 mV (Currently stable for now)
GPU & iGPU Unslice : 120.1 mV (Also stable)

And I also underclocked my cpu when some cores are used

1 cores active - 4.2 GHz
2 cores active - 3.9 GHz
3 cores active - 3.6 GHz
4 cores active - 3.4 GHz

By the way, should I put 7.5w or 15w for the Type-C Connector Power in the BIOS?



Turns out my game kept crashing so I changed it to -130.9 mV and -117.2 mV
I dont see any overheating, you said you are playing games. The temps look ok by me, it says 84 or 88C.
You said you play games, the processor and graphics card are both integrated to the same chip. They share both heat and heat sink, and being a low voltage processor of 15w, the cooling is not going to be the best.
 
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System Name Dell Latitude 7490
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No. Try again. Spread a very thin and even layer. Than tighten the screws according to the numbers on them. Do as many attempts as needed until reaching temp readings on all cores with a difference less then 7-8 degrees Celsius. I would choose a better paste with higher max working temp.

Does silver mx-4 have a curing time? I already tried repasting few times and the temp doesn't drop.

I dont see any overheating, you said you are playing games. The temps look ok by me, it says 84 or 88C.
You said you play games, the processor and graphics card are both integrated to the same chip. They share both heat and heat sink, and being a low voltage processor of 15w, the cooling is not going to be the best.

Yeah but the performances are throttling at 15w. The temp didn't exceed 80c for this one so I put it to 17w.
 
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Does silver mx-4 have a curing time? I already tried repasting few times and the temp doesn't drop.



Yeah but the performances are throttling at 15w. The temp didn't exceed 80c for this one so I put it to 17w.
It starts throttling at 15w because you have a 15w processor.
The TDP in that link says 15w.

Does silver mx-4 have a curing time? I already tried repasting few times and the temp doesn't drop.



Yeah but the performances are throttling at 15w. The temp didn't exceed 80c for this one so I put it to 17w.
That I know of, mx-4 doesnt have a curing time.
 
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