[SOLVED] CPU overheating issue

[laurens344]

Hey all,
Would like to ask for some input on the reason why my CPU is randomly heating up to 80-90deg.C when idle, after which it returns to 40-50deg.C. During games, even if CPU usage is around 30-40%, it easily heats up to 100degr.C. After closing the game, it does cool town to 40-60 within just a couple seconds.
PC specs:

• PC: msi mag codex x5 11td-626mys
• Bought in oct 2021; running on Windows 11
• CPU: Intel Core i7-11700KF
• GPU: GeForce RTX 3070
• RAM: 32GB of DDR4 3.200MT/s
• MB chipset: Z590
• Solid State Disk (M.2)
• Power supply: 750W
• Cooling: liquid cooled (MSI Mag Coreliquid)

Some more info:

• No dust on any of the fans
• Places on top of desk, not perfect placement for air flow but it has about 20-30cm or more space on all sides (especially top)
• Even when fans start rotating at high speed, cool airs comes out of all places where fans are positioned --> to me this sounds like a problem with heat transfer from CPU to the liquid cooling or the cooling liquid not transferring the heat to the fans?
• Temperature reading same through MSI control center or HWMonitor
• Never had it shut down (potentially due to high temperature?)

What I found online:

• Re-apply the thermal paste
• Potentially AIO pump problem? MSI control center says pump fan and cpu fan are running though
• Could there be an issue with the temperature sensor too? Causing the fans to just go crazy?

I think re-applying the thermal paste is something I can do, but it would be nice to get some tips on how to check for pump problems or potential other things that'd cause CPU overheating!

Thanks for some tips!
Laurens

 

[Phaaze88]

it would be nice to get some tips on how to check for pump problems

While there is a load on the cpu - either the previous game or Cinebench R23 - feel both tubes.
If you can hardly tell a difference in how they feel, then all is well.

If you can clearly tell one tube is warmer than the other, then there's a problem. There's blockage, or air sitting somewhere it shouldn't be, either in the cpu block or the radiator(where the pump is).
Control Center doesn't tell the whole picture - it at least tells you the motor/pump's not dead. Doesn't confirm blockage or trapped air though.

 

[steveb1976]

where do you have the AIO radiator fitted(top or front of case), and it is setup to suck air in , or blow air out.(you would need to check orientation of the fans).

 

[laurens344]

The AIO radiator is fitted on the back and sucks air in. There are then 2 additional fans on top that blow air out.
It was the default setup of the prefab pc.

 

[laurens344]

If you can clearly tell one tube is warmer than the other, then there's a problem.

There seems to be a small noticeable temperature difference between the two, but not in a way that one was very warm and the other cold.

 

[Phaaze88]

Then there's some debris moving around in there occasionally sticking and slowing down the liquid flow, or air is making it's way to the cpu block.

You can maybe try removing the radiator and shaking it around a little. Won't really do much for debris, but it might break it up. Since the loop is closed, it can build back up again.
You could be looking to RMA the cooler. There's not many ways to troubleshoot+repair these coolers.

 

[steveb1976]

try installing an app called "Core temp" it will show you the real time temps of you cores(all the cored). them try running game with the app running in background and then check it. will tell you the lowest and highest temps. .

you said you have repasted the cpu, what paste did you use?
do you have front fans on your case?

 

[laurens344]

you said you have repasted the cpu, what paste did you use

Not yet, but I will (with Arctic Silver 5 3,5g).

All of the 8 cores are somewhat within the same range. Biggest difference between 2 cores is about 2-3 degrees Celsius. So during a game, they often spike to 95-100 after which the fans turn up to max and reduce temperature to 75-85 again (and then repeat; rather than keeping it stable).

There are no front fans on the case, only back and top. I get a suboptimal airflow might be a problem with high-end games/programs, but even when opening something lighter (like chrome), CPU temperature can spike for a couple seconds to 80-90.

 

[Phaaze88]

How fast does the pump run usually run? Running at higher speeds, like 80-100% respond more smoothly to sudden spikes.

 

[steveb1976]

the 120mm AIO is probably not powerful enough to cool the cpu properly. . i had a 240mm for my old i5 9600k 2 years ago,which worked. you might need to get a 240mm aio (they can be cheap).

 

[laurens344]

Thanks for your input both! I think I will re-apply the thermal paste and reseat the AIO (and give it a little shake) . If that's not the fix, I'll probably replace the cooling system.

 

[Zerk2012]

Thanks for your input both! I think I will re-apply the thermal paste and reseat the AIO (and give it a little shake) . If that's not the fix, I'll probably replace the cooling system.

That is not going to help they used a cheap case with poor airflow and the cooler is not good enough to cool that processor.

 

[laurens344]

That is not going to help they used a cheap case with poor airflow and the cooler is not good enough to cool that processor.

Well yes maybe, but that does not explain the fact that no hot air comes out of the system at all right? If the cooling system is inadequate to optimally cool the CPU if its under stress, you would atleast expect hot air to come out? Even if the CPU is running at 5-10% capacity, it can heat up to 90°C or higher.

 

[Zerk2012]

Well yes maybe, but that does not explain the fact that no hot air comes out of the system at all right? If the cooling system is inadequate to optimally cool the CPU if its under stress, you would atleast expect hot air to come out? Even if the CPU is running at 5-10% capacity, it can heat up to 90°C or higher.

Yes it should be putting out heat, but they put a 120mm AIO on it not good enough.

 

[laurens344]

Re-applied thermal paste, did nothing.

Looking at the AIO again: I notice that when it's heating up to 100 degrees celsius (the AIO fan goes crazy but still cold air comes out of it after air passes through the radiator), temperature quickly drops when I would tap both hoses between the radiator and the pump (to about 80 when running a high-demand game). I tried before to flick the radiator around and always keep it higher position than the pump. No after tapping the hose on a regular basis, warm air starts coming out of the CPU fan so I presume heat transfer is better now. Might suggest still some air trapped in the pump or in someway limiting the flow? One hose is warm whilst the other is cold, which would make sense right? As a warm flow would leave the CPU and a cold flow would leave the radiator?

Cheers. Guess I'll keep tapping for a bit 😉 (and look for a new AIO in near future probably)

 

[Phaaze88]

the AIO fan goes crazy but still cold air comes out of it after air passes through the radiator

Why does cool air come out during this? The heat is not getting to the radiator.
And why would that happen? A number of reasons:
debris in the loop impeding or blocking flow
dead pump motor
cooler cold plate not properly mounted to the cpu
air in the cpu block or the pump

temperature quickly drops when I would tap both hoses between the radiator and the pump

So you're either knocking away clumped debris, or an air pocket lingering somewhere it shouldn't be.

I tried before to flick the radiator around and always keep it higher position than the pump.

You're not doing what you think you're doing here. You're exposing the pump to air by suspending it above the cpu block.
With Msi's MAG Coreliquids, the pump is in the radiator(that little black cube).
With their MPG and MEG Coreliquids, it's Asetek's traditional pump in water block design.

Honestly, 120mm is not large enough for pump in radiator AIOs. Air will inevitably get to either the pump or cpu block, neither of which is favorable; one reduces performance and one reduces performance and lifespan.

Might suggest still some air trapped in the pump or in someway limiting the flow? One hose is warm whilst the other is cold, which would make sense right? As a warm flow would leave the CPU and a cold flow would leave the radiator?

Perhaps it makes sense when the cpu isn't really doing anything, but under loads, that is 'too fast' for an AIO, but not for an air cooler.
Liquid has higher thermal capacity than air, but it turn, it takes longer to cool down. That energy does not just up and vanish at the radiator in the first loop. It's going to go through cycles before that happens.
There's the energy from the cpu, plus energy from just about everything in front of the little 120mm AIO that passes through it, with the biggest threat being the gpu when it's active.

Air coolers also have liquid in them, but we're talking literally a few drops.

 

[laurens344]

With Msi's MAG Coreliquids, the pump is in the radiator(that little black cube).

Oh this is a good point ha! Thanks for that info.

I will look for a 240mm or 360mm AIO in combination with a proper tower case!