Question i7-8700k runs at 80c while idle ?

SophusVir

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Jun 1, 2015
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CPU: i7 8700k
Cooler: ibuypower deepcool gamerstorm rgb 240mm castle 240ex liquid cooler
Core speed: 4500mhz
Core voltage at load 1.1
Load test software: None
Temperature software: Core Temp/Bios
Load & idle Core temperatures: 60c idle, Load 99c-100c
Memory: 3400 vengence 16x2
Motherboard: AsRock 390
Graphics Card: Nvidia 3070
Ambient temperature: 65F

No idea how it got to this point, just noticed this lately, the system had gotten very slow. Replaced the Video card and ram then noticed on my bios my cpu temps were hitting yellow on idle. It hits 60-70c just sitting with like 1% cpu usage. Any ideas?
 
A few:

Do you take this machine outside and blow it out on a regular basis? When was the last time it was actually torn down and cleaned?

Is the AIO inside the machine the same one you purchased it from ibuypower with?
240 Castle has, IMO been a pretty good cooler. I am using one now. They are getting a bit older, so it might be of consideration that it is failing.

Clean it if it needs it. If you still have issue, consider swapping out to an air cooler as a test to see if it will run cooler.
 
Check the pump is still working, what's the RPM on HWMonitor. Also have you tried repasting?
We just discovered the problem today. While putting in new ram we noticed the cpu was running hot via the bios and now monitor it via CoreTemp. As for the pump, how would I tell if the pump is still working? I know the fans on the pump run but how do I check the pump itself? I'll have to look into HWmonitor.
 
A few:

Do you take this machine outside and blow it out on a regular basis? When was the last time it was actually torn down and cleaned?

Is the AIO inside the machine the same one you purchased it from ibuypower with?
240 Castle has, IMO been a pretty good cooler. I am using one now. They are getting a bit older, so it might be of consideration that it is failing.

Clean it if it needs it. If you still have issue, consider swapping out to an air cooler as a test to see if it will run cooler.
Yes. Everything besides the GPU and the ram are factory. It gets cleaned out regularly via canned air. It has never been fully taken apart and cleaned no. I'll take a look and see if it is dirty.
 
We just discovered the problem today. While putting in new ram we noticed the cpu was running hot via the bios and now monitor it via CoreTemp. As for the pump, how would I tell if the pump is still working? I know the fans on the pump run but how do I check the pump itself? I'll have to look into HWmonitor.
On HWMonitor, it will have the RPM for both the fan and the pump. You will want to check that the pump is spinning at the RPM expected for that cooler.
 
Ok so we took apart the cpu/cooler and found it was pretty gummy. Resilvered and cleaned up the cooler but it still idles at about 48c and hits 80c+ while running something like Division 2
 
Useful video.


Basically if the pump fails there is no noise or vibration. The air from the radiator is room temperature and one of the tubes between the CPU block and the radiator is hotter than the other. There can be other issues, like a mounting issue, thermal paste issue or someone left the plastic protector sheet on the AIO cold plate.

Also the pump power cable can become disconnected, so the pump may have not failed. Also there could be a hardware issue with the AIO. Sometimes they become dry inside, get blocked with crap or the pump fails. A radiator can become completely blocked up with dust and no air can make it through.

Fixing a hardware fault can be a simple as replacing the AIO or repairing it yourself.

 
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Useful video.


Basically if the pump fails there is no noise or vibration. The air from the radiator is room temperature and one of the tubes between the CPU block and the radiator is hotter than the other. There can be other issues, like a mounting issue, thermal paste issue or someone left the plastic protector sheet on the AIO cold plate.

Also the pump power cable can become disconnected, so the pump may have not failed. Also there could be a hardware issue with the AIO. Sometimes they become dry inside, get blocked with crap or the pump fails. A radiator can become completely blocked up with dust and no air can make it through.

Fixing a hardware fault can be a simple as replacing the AIO or repairing it yourself.

I do have one line is hot and one is cool. The fans still run and the power only has 2 power lines. One to the LED and one to the fans/pump. Are both lines supposed to be hot the temp coming out the back where the thing is mounted feels cool.
 
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I do have one line is hot and one is cold. The fans still run and the power only has 2 power lines. One to the LED and one to the fans/pump. Are both lines supposed to be hot?
Coolant should only be a little hotter on one side. If you can tell that one side is hot and the other is cold. Then that could mean no flow is taking place. So what happens is you have heat convection, so hotter liquid creeps up one pipe and colder liquid is drawn down the other. The radiator doesn't appear to be passing any heat to the air. So you get 80c+ CPU temps and the air from the radiator is still like room temps. Its basically cold but one pipe is hot which impies the hot liquid is not passing throuh the radiator.

There could be a number of reasons for this, pump failure and a blockage are two that come straight to mind. If there was dust blocking the radiator then the radiator would heat up and both pipes would become hot.
 
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I do have one line is hot and one is cool. The fans still run and the power only has 2 power lines. One to the LED and one to the fans/pump. Are both lines supposed to be hot the temp coming out the back where the thing is mounted feels cool.

Yup. Liquid going to the radiator ought to only be a couple degrees cooler than the liquid coming from the radiator. That's why you need it circulating quickly for cooling to happen.
 
How I classify overkill radiator setups: (Full load)
Extremely overkill: Delta T < 3C
Very overkill: Delta T < 5C
Overkill: Delta T < 10C
Reasonable:Delta T < 15C
Everything else: MORE RADS, I NEED MORE!!!
Source

All I know is under 60c is safe for my setup at full load. DT is the difference between the loop temps and the air temps. With mine there is normally little difference between both sides, cold and hot side of the loop. There is a problem if one side is like 60c and the other is over 20c colder. The liquid is ment to be flowing quickly. So both sides should be close, well as far as I understand it. After awhile liquid temps should normalize in the loop.

Water temperatures in a stabilized loop, amazingly, are very similar anywhere in the loop. There is only a 2-3°C maximum difference between the radiator out temperature and the CPU out temperature; this has been verified by Skinnee. Source

The air comming out of my radiator gets warm when running prime95 small ffts. The pipes are rated as safe upto 60c. So hitting that temp or higher is not good for the loop. If heat is pooling on one side then there could be a flow issue. The pressure difference will cause some flow to take place as the warmer liquid expands and moves upwards. This should draw cooler liquid towards the heat source. The key take away is this flow is very small. So one side will be far hotter than the other.

Just my take on things. The great paranoia with any liquid cooling system for a PC is leaks. Never leave a system running with a liquid cooler that has issues. I would remove any liquid cooler that has issues from my system. It can then leak safely all over something I dont care about.
 
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I removed the gunk and it runs cooler while idle but soon as I run anything it hits back to 100. Would the cpu also be damaged? and if it is how would I tell?
Reaching a very high temp like that won't suddenly break the CPU but it will gradually degrade it over time.
In terms of the cooling solution, I believe in some circumstances AIO's can be repaired. However I would just replace it at this point.