System and system interrupts high cpu usage issue

[Jussi_]

Yesterday I realized that my desktop wasn't performing well in the games I play. I noticed that system and system interrupts (also service host: local service, but i managed to fix that) were using a huge junk of my cpu. Core Temp showed me that the load on my core #0 was over 90% and cores 1-3 between 50-90%. also my idle temps were over 60C when theyre normally around 30C. I thought either win10 had screwed something up or I had when I was tweaking it. At this point I just wanted to reinstall windows since I could find any easy fix. I couldn't reinstall win10 tho (gave me errors) so I clean installed win7. I noticed the same thing in win7 that system was using over 30% of my cpu and the overall load was way too high. Granted I didn't install any drivers at this point because my plan was to update to win10 immediately, so I have no idea if it was because of that.

I managed to clean install win10 a little while ago and updated all my drivers so far, but yet the problem exists. After i managed to shutdown few services, the service host, local service cpu usage stopped and now my temps are around 50C at idle, but my core #0 is still on over 90% load, but other cores around 10-40%.

Any idea what should I do? Is this a software or a hardware issue? my pc is about a year old.

specs:
i5 4690K (not overclocked)
Asus Z97-P motherboard
MSI geforce GTX 970
kingston 240gb hyperX savage SSD
Kingston 16gb HyperX Savage DDR3 1600mhz
corsair 650W psu.

 

[Colif]

Perhaps check to see CPU fan/heatsink aren't full of dust. Check case fans as well.

The fan speeds should be coordinated by the BIOS but installing motherboard drivers should also fix them. Since you had no drivers installed I have to assume you weren't using AI Suite 3 to control fans.

Did you get an update to windows this week as system may have been installing downloading that. Part of process was to run the Malicious software removal tool but it should have been marked as that, not system.

 

[Jussi_]

I still have no idea what the issue was, but everything seems to be fine now... The problem seems to have disappeared on it own.

 

[ihriss]

Similar issues here, except for me it's only the 'System' that's hogging the CPU. The problem has been stagnant for maybe ~3-4 days now. I even let the pc to run overnight to see if it would help, but it didn't.

In task manager the process called "System" is constantly using ~35% of CPU. The usage is pretty much flat all the time.
Process explorer shows that "System" is using ~25%. System interrupts or any other process underneath or anywhere else shows close to 0%.

What I've tried:
Rebooting x times, no effect.
Run "sfc /scannow." Nothing found there.
Run antivirus scan, nothing found.

The PC is an Acer vn7 laptop with i5-6300HQ cpu and the 64bit home version of win10.