Z170M-ITX/ac System Interrupts high CPU usage

I don't have an immediate solution or fix for your problem, since I've never encountered it in an ASRock forum or experienced it myself. So I'll be asking questions about things you may have already checked or done. I know you are sick of dealing with this, so please remember that we don't know what you've done to diagnose this problem.

Two quick FYIs: Yours is the first post I've ever seen about this problem for any ASRock board. There is a new UEFI/BIOS version for your board, 1.30 that you can find below, although if you've tried the 1.20 UEFI without any change, 1.30 likely won't change anything as well.

http://www.asrock.com/mb/Intel/Z170M-ITXac/?cat=Download&os=BIOS

When you install Win 7 and Win 10, what drivers do you NOT install?

What monitoring tool is telling you that those two Windows services are using ~50% of the CPU resources, Task Manager?

If you check Device Manager, in System Devices, there are at least two entries for ACPI devices. Ever look at those?

Did you ever run from a system CMD prompt (Admin) the msinfo32 system information too? In its Hardware Resources section, you'll find several categories of potential information and clues about that problem. The Components section has a Problem Devices section, and the Software Environment has a Services section that might also provide clues. The last entry in that section is Windows Error Reporting, that again may have useful information.

Ever check the Windows Event log, among others, for entries that might reveal the problem?

When a CPU is under a constant ~50% usage load, it will be at a higher temperature than at an idle, low load condition, regardless of the CPU cooler. My point is that level of CPU usage will be detectable by the CPU temperature.

If we are using the UEFI/BIOS UI, we basically know what the CPU temperature will be; somewhat above the  post Windows boot idle temperature, right? While in the UEFI UI after about 15 minutes, if the board itself is causing the high CPU usage, maybe you would see that reflected in an increased UEFI UI CPU temperature. That would tell us the board is likely the problem, and an RMA or replacement is necessary. Otherwise it could be a software or driver issue.

Is there any driver(s) that you install that are the same version in Win 7 and Win 10? For example, Intel recently removed the IRST version 14.5 driver from their download pages, apparently due to several major bugs. That driver version was supplied by most if not all mother board manufactures with their latest boards.

I understand that you are very frustrated by a difficult problem, which may be impossible to fix IF there is something wrong with that board.

But your experience with one board from a different manufacture should not be an indictment of that manufacture is general, or even one model of a mother board from that manufacture. I've been posting in ASRock forums for almost four years and have never seen a post about your problem. I've also used ASRock boards of every Intel CPU/Chipset generation since the 7 series was released. That is nine different ASRock boards, and none of them have this problem. They all work fine to this day.

Thanks for the reply. The board has found a new home. MY TRASH CAN.



Edited by Rick540 - 21 Sep 2015 at 3:52pm

I kind of wish I hadn't modded the heatsink but oh well. I could have returned it to Newegg for some money back. I'm not rich by any means. But then again I didn't foresee a total hardware failure. I've built my own PCs for myself and others for the past 12 years or so and never had a problem like this. You win some and lose some I guess.

Do what I did...

Get an ASUS.