[SOLVED] i7 8700k jumpy temperatures

Apr 11, 2019
Hi there thanks in advance for your time and effort in helping me out.
I will say it as best I can and short and sweet and if I am not clear please let me know.

I bought a new Z370 Motherboard and a new i7 8700k CPU about 1-2 weeks ago. As soon as I finished installing/building my PC with the new components and installing windows from scratch I immediately tested the Temperature of the CPU cores and frequency with MSI afterburner and corsair link through the power supply software and the temperature of the motherboard and I saw that they looked fine (by fine I mean cpu running at 33-36c) and so I did not bother anymore with testing but now I know I should have!, because I cannot actually remember what my cpu temps where on all cores and testing it further by running a youtube video or some basic task to see how the CPU responds in regards to frequency and temperature.

My issue is this, because now I DON'T know and did not record what the normal/first temperatures where while just at 'idle' on desktop or even when it launched a more demanding task, I cant compare or trust what my issue is now to when I first booted up the system fresh. My real issue is that #1. due to an error that appeared on screen 2-4 days ago(I can provide picture), #2. when opened a youtube video, it looked like it was playing in a slower way(the frame rate) and I thought the CPU frequency was at issue or temperature, #3. a CPU load spike in task manager to 100%(doing something that I still don't know if it was good or not, #4. installed a older 180mm/200mm fan to my case again(its old but looks to work fine) which as all this chain of issue began, this 180mm fan was ramping up and down in a way that I had not heard before (the way I set it up in bios and also a new cpu and motherboard, no surprise really)

All of these issues happened in 1 day so I freaked out and I checked CPU temps and this time I saw the cores going from 30c to 50c just like nothing, I'm talking not a slow creeping up but just in fast movements spiking to 50c from 30c and all the while cpu is doing nothing or just light youtube video watching. The 20c spike like nothing from maybe 3 to sometime all the cores doing the same tells me maybe something is wrong, and the bigger issue is that I cant remember what my baseline/fresh temperatures where and how exactly CPU performed in different scenarios since the first windows install to compare if that is normal now or not and it has change and something is wrong.
Since then I have done these things, #1 fresh installed window 10, #2 took motherboard out of case and put on MB box as I thought new air cooler was heavy and pulled away from cpu or cpu cooler was not contacting cpu properly or thermal paste was applied wrong, and now I have motherboard laid horizontally. Doing all these things has shown no change in the way the temperature of the CPU spiked up to and the speed in which it did it and the cores in which it did it on.

I'm so sorry for the story and now I see I could of just asked this simple question and say the 'story is optional'.
My question is: anyone who has a i7 8700k, can you please send me a video or picture/s of how your cpu behaves regarding temperature on the cores when just at the desktop (preferably with nothing unnecessary running in background and also while opening file explorer and other windows apps?.
Or tell me if my temperatures are normal for this chip. I know I have not provided pictures or good evidence of what im saying but I first want to find out if I even have an issue with this CPU or not compared to you guys.

Main point as I have said ALOT: My CPU temps on sometimes 1 or 2 cores or sometime all, rise up by 20 degrees and back down in 1 second or less and it does this while opening file explorer or windows is scanning for viruses or Im watching a youtube video, and YES it does this even while I play a game ( Warface or Apexlegends), is this normal?
GPU temps don't rise this way for me, is it normal for CPUs to do this and specifically with this 8700k? Please let me know what software to test it on, how to test it(to your liking) and should i post pictures/videos/ the softwares file/s as I want to also show you guys what I mean as that is best as I can fail in my explanations.

Thank you all so much, I hope to hear/see from all you 8700k owners and other experienced members.
Have a Great day, Chris.
I don't really see that as abnormal. CPU core temps change very fast.

If I wasn't at work I would send you a screen shot of some of my CPUs temps and you would see the temps jumping....and I think 20 degrees is pretty negligible if you are starting out reasonably low.

As far as jumping at idle....my CPUs generally don't jump much at idle....but maybe you have something running that's causing it.

If the temps are good throughout this jumping.....and you don't see any performance issues......I might not worry about it.

You could also try disabling services etc and see if you can locate what''s causing it.....but it might just be a waste of time because it might be normal.


Mar 31, 2019
Basically what is happening is your cpu is engaged to do some processing, then activity equals heat, then the temperature goes up, then the cooling fan kicks in to steady the temperature. This goes on back and forth and is totally normal. The only time you have to worry is if you see temperatures over 70c staying high.. Then you have a cooling problem, not a cpu problem.
Everything seen as you described is normal....and has been for years.

As the processor is ramped up from idle/800-1000 MHz at 30C when moving the mouse around, however once opening a window, launching an application, etc., the clock speeds will jump many times per second over assorted cores nearly instantly, with temps in the 40-55C range...and one can watch clock speeds vary wildly from 800-1000 MHz all the way to 4700 MHz for an 8700K...

Under a heavier more constant load, you will likely see 65-70C...; launch CPU-Z, select 'Bench' tab, and then 'Stress CPU" at bottom, and observe temps (most folks do this via HWMonitor) and clock speeds shoot up instantly to 60-70C as all cores/threads are loaded... (Gaming loads will likely not exceed 55-65C)

I've read where at least a few folks were saying some of the MSI Afterburner portions were causing clock speed/lack of proper idle issues when in normal Balanced Power mode...
Apr 11, 2019
Thanks Jay, Fix and mdd for your great help, it gives me a lot of confidence. I will do everything you guys suggested and report back if any issues.
I don't know( should have known by reading forum rules if any) if I need to report this issue as fixed but it definitely is for now thanks to you guys :) but feel free to make this issue as solved and great help, thanks!.

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