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Question

CPU getting VERY hot

May 13, 2017 5:59AM PDT

Hi. Hope you can help
Specs
i7 4790h CPU
GTX1070 GPU
Hyper X fury 16gb ram
Corsair H100iV2 watercooler
Corsair HX750i PSU
Z975s sli Krait edition
NZXT h440 case
240 SSD + 2tb Hdd
Never been overclocked
My son and I built his PC last year and all was fine for 6 months, then my son told me the CPU was overheating when nothing was on.
From cold the CPU would register over 90degs via realtek within 2 minutes and the fans on full,
He was playing a GTA mod one night and the rest is history
We've removed and resealed the cooler with new paste but no joy. Cant use pc for more than a couple of minutes for fear of permanently damaging the cpu
any suggestions please

Discussion is locked

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Answer
Heat
May 13, 2017 6:37AM PDT

What is a 4790h?

Is the cooler attached to the cpu proper?

Is the cooler working?......pump/fluid/exhaust fan.

90 degrees what, C or F?

Try a different temp prog or there might be a monitor in the bios.

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Amendment to CPU details
May 13, 2017 7:47AM PDT

Hi Bob
Thanks for the reply, yeah sorry about that, typo, meant to type i7 4790k from intel. Yes, the cooler is properly attached to the cpu. we have removed and refitted it with new thermal paste to ensure it was on properly and make sure the paste wasn't cooked

Its hard to tell whether the cooler is fully working, its very silent in its operation, but within 15-20 seconds you can hear the fans increase speed and see the temp increase on the dial, we switch off when its in excess of 90 degrees Celsius and yes the cpu mount is hot, we can feel it with the back of the case off.

We thought about taking the water cooler off and fitting the cpu heatsink but thought that would be going backwards, besides we think the cpu shouldn't be getting that hot at idle in the first place.

don't think a new measuring prog is necessary as it obviously hot

Thanks
Ian

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I have heard
May 13, 2017 7:55AM PDT

a couple of Pro's here tell others to keep the side/back cover off and use another fan blowing inside the case to see if it makes a difference

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I meant
May 13, 2017 7:57AM PDT

I have read not heard Blush

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Heat
May 13, 2017 11:52PM PDT

If your bios has a hardware monitor use it.
See if it agrees with what you windows monitor shows.
While in the bios verify you are not overclocking.

Next step is to fit the stock cooler and test.

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Answer
Besides what Bob_B wrote.
May 13, 2017 7:46AM PDT
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Water cooler?
May 13, 2017 8:14AM PDT

Now it's a bit more of a problem since how do you check fluid levels?

If you have another cooler, try that.

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Water cooler
May 13, 2017 9:47AM PDT

Yes we were thinking of fitting the heatsink provided with the cpu.
Q. whats the normal operating temp of a cpu supposed to be at idle?

My sons in the run up to his A levels so were not doing anything with it at length with it.
BTW the cpu load is showing 0% as its not doing anything

???
Thanks

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There is no normal.
May 13, 2017 9:59AM PDT

It varies from machine to machine, influenced by ambient temperature and system design. Also, if there is malware such as a rogue bitcoin miner or torrent app, you won't see any idle temperature drop.

Here on a desktop I see under 50C after a machine is booted and doing almost nothing after 20 minutes. So while that's a number, it's not normal as it's more of a range.

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No normal!
May 13, 2017 11:25AM PDT

Thanks again
Whilst you say there is no normal, this I would say is definitely abnormal
I've never seen a CPU gain so much heat so quickly whilst doing nothing (relatively)
I have toyed with the idea of some malware or software conflict but we cant let the pc run for long enough to check.
Will try to run in safe mode to see if that work but cant remember how to run in safe mode with Win10 F8??

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Try it with no OS?
May 13, 2017 11:47AM PDT

Head to the BIOS screens as many show temperatures today and see if a no-OS report works.

Given it's water cooled and I see no reply from you about coolant checks, I'd install a normal heatsink next.

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(NT) Tried "safe mode"
May 18, 2017 5:42AM PDT
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Again...Tried "safe mode"
May 18, 2017 5:47AM PDT

As its my sons PC and I'd written down instructions on what to do, He took his time going round the houses logging on and by the time he got into safe mode the fans were already sounding like they were taking off so we switched off again, as we had no time to look at it in depth we didn't try anything else so its a case of well try at the weekend to fit the heatsink instead
Thanks for your efforts all, will let you know what happens