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I've seen other posts about this but since I have a more information about the situation I'm thinking I could use some help to isolate the issue rather than reinstalling every single driver the trial and error way. (Which I will resort to if nothing else helps but I really do not want to go fetch the drivers for every single thing in device manager)
There is a system thread under the name "ACPI.sys" taking up around 12% of the CPU. I've done some research and it seems this is a driver issue most of the time.
The thing is, I haven't touched any of the WLAN/Audio/USB drivers or anything of the sort, I didn't do an upgrade to those drivers or any other drivers, everything worked fine before, now it simply doesn't and I didn't do anything in that field.
I can isolate the issue by stating this happened after a CMOS reset due to overclocking too high, the system is stable now. I checked in the programs/features list and sorted by install date and it turns out some Intel drivers were installed recently, I assume that they were part of either AIDA64 or Intel XTU as I didn't manually install them. One of them was called "ACPI Driver Install" or something along those lines so I immediately suspected it and attempted removing it, but with no effect. I then saw another driver called "Intel Watchdog Timer Driver" I then tried uninstalling that but apparently it won't uninstall as nothing happens when uninstalling, no menu, no nothing.
I set my CPU clock speeds to default and uninstalled XTU to see if maybe it was the issue, but still nothing. Since I'm currently running a laptop with a heavily restricted BIOS I think the worst case scenario could be that the CMOS reset altered a value set by the manufacturer (Asus) which normally you can't change using the BIOS as it's restricted and lacking options, meaning there is absolutely no way as far as I know to set that hypothetical value back to what it was. I doubt it, but it's the only thing which correlates to the CMOS reset.
I tried booting into safe mode but the CPU usage stayed the same. I also saw on another forum that someone asked if MSI Afterburner was used as if it held some sort of relevance which leads me to think maybe MSI Afterburner is somehow involved in this too but the user in question didn't have it installed so there was no elaboration on that.
ACPI.sys Itself seems to be a power/temperature regulator of some sort, I heard it's responsible for thermal throttling, if this is true, it could be that it conflicted with XTU in some way.
I know it's not exactly the safest thing to do but I tried killing the thread via process explorer but it couldn't kill it, even with admin privileges, nor could it actually access much information about it, leading me to believe it could also be a corrupted install of something Intel involved?
I'm thinking of making a copy of ACPI.sys and then deleting it from the System32/drivers directory to prevent it from starting as I don't think it's a critical component, as I said, from what I hear it's just a power/thermal throttle regulator but I'm hesitant to do so as it could actually be a critical component.
I also thought maybe I could look in the services panel, it could be a toggleable service but I couldn't find it / it's not there.
If it's of any relevance, I'm running Windows 10 1607 / 14393.953 The laptop model in question being an Asus G752VY
The last thing I want to do is flash the bios or have to re-install every single driver but I guess I'll have to if there is no other option.
Any thoughts or suggestions would be highly appreciated.
EDIT- It is not a duplicate question, I've stated I'm aware that this has been answered multiple times but each time this is asked, the solution seems to be specific to the situation. Other questions of the same type don't help at all as they're not the same situation I'm experiencing, just the same effect. For one person it was the rapid storage drivers, for the other it was a CMOS reset that fixed it, for another person it was a BIOS update, the answer is different all the time. The only thing that's the same is the effect, which is the high CPU usage, but the answer is not the same every time and heavily depends on the situation, my situation being entirely different with different information on the problem, hopefully leading to a resolution specific to my problem.
EDIT2- I found a temporary workaround to the problem which at least stabilized my CPU usage, but doesn't really permanently solve the problem. As I've stated, I tried killing the thread but I wasn't able to kill it and it denied access. I recently found another program other than Process Explorer called Process hacker which is similar but has a feature that Process Explorer doesn't, and that's the suspension of threads. I suspended the ACPI.sys thread with admin privileges successfully and now my CPU usage is back to normal. This isn't really a solution and I'm still hoping for a proper solution to the problem but for now at least my computer is operating fine.
EDIT3- I noticed after a while and a couple of reboots that ACPI.sys wasn't sucking the life out of one of my cores anymore. As I've stated in the second edit I used a program (process hacker) to suspend ACPI.sys which didn't give me an access denied error like attempting to kill it does. I kept it suspended for a while and then just forgot about it entirely, I remember rebooting for entirely different reasons and I didn't re-suspend ACPI after the reboot yet it stopped taking up CPU usage. It seems as if suspending ACPI using process hacker and then rebooting a while later worked. For anyone else with this issue I recommend just keeping the process suspended using process hacker and waiting a while then rebooting, if that doesn't work then keeping it permanently suspended is a valid workaround.
follow the suggestions regarding acpi.sys in my answer in the duplicate topic.
– magicandre1981 – 2017-07-03T17:12:58.690I tried all of your suggestions for ACPI.sys. The temperatures are stable and not high (30-40c), I updated the BIOS, I loaded the default settings, I disabled the battery, and I haven't done anything touched the DVD drive. Nothing is working. I tried disabling every device in device manager, I reinstalled Audio, Video, Ethernet drivers, I unplugged everything, uninstalled recently installed items, e.g. drivers/other stuff, I deleted every single intel driver and reinstalled. Nothing. – Shayna – 2017-07-03T23:19:33.647
in this case you have to do some trial&error approaches until you find a solution. My suggestions are a sum of things users figured out over several years. I wrote everything that I currently know to fix it. – magicandre1981 – 2017-07-04T19:46:06.790
Strangely enough as I stated in my second edit, I used a program similar to process explorer to suspend the process, after suspending it, it stopped using CPU usage even after a reboot and ACPI.sys isn't suspended anymore, seems like suspending it then rebooting fixed it? Since this isn't really a listed solution, can this be added to the list of solutions on your original page? – Shayna – 2017-07-05T06:50:54.113
ok, I've added your workaround to my answer in the duplicate topic. – magicandre1981 – 2017-07-05T17:42:47.497