[Solved] Intel i7-6700K being bottlenecked by Windows Updates! HELP!!

[SpecsGuy]

This is the most horrible issue I've ever faced. I spent about 8 hours in total trying to fix this but ended up formatting the entire system a few times and couldn't get it fixed (unless I never download any updates or only some of them that do not cause the problem, which I don't know anything about).
Not sure if you believe this but when I first upgraded from FX-8320 to i7-6700K, I noticed (using the "CPUID HWMonitor" software) that the i7 reaches 100% max under the "Utilizations" section for all the the CPU #0-7 (all of them). Everything was extremely smooth, Twitch video on Source quality seemed to be using my system, 0 lag, 100% smooth, including in games and the PlayStation game emulators. Now not even a single one of them can reach 90% while the rest are stuck in 60s and 70s.

Now the stuttering is back like it was with my old FX-8320 (except it's slightly better now thanks to i7). I thought FX was originally like that but no, it's the damn Windows Updates. After I downloaded and installed about 200+ updates, it began throttling everywhere including Twitch at full screen, browsing in general and in gaming.
The problem is known here but I can't find any solution!! 🙁 I just have to avoid the Windows Updates but that doesn't help my system either since there are some that really help such as the Framework updates, etc. Now even though I've only installed about 50 updates, the 100% performance is gone. It's only going away after I download Windows Updates.

Now my CPU is underperforming. While gaming it's using about 60-89% of its performance per core instead of 100 each. I beg you guys if you know a solution that can really help and bring back my CPU the way it was. The only solution at the moment is to format and avoid the Windows Updates.

Also I haven't overclocked or even touched the motherboard BIOS from the beginning.

System specs:
Intel i7-6700K (stock speed)
MSI Gaming Z170A M5 motherboard
G.SKILL TridentZ Series 16GB (2 x 8GB) DDR4 3200
Radeon HD 7870 2GB
WD Caviar Blue 1TB
700W Power Supply
Windows 8.1 Pro 64-bit

P.S. I see lots of benchmarks on YouTube showing this CPU's cores using 100% of their performance and the gameplay is smooth. It was like that before the updates. 🙁


Sorry for the wall of text!! Best regards.


SOLVED / FIXED
This problem had nothing to do with the CPU cores usage/utilization. I went to my motherboard's BIOS and disabled an option called "Intel Adaptive Thermal Monitor" that was throttling my CPU. For some odd reason my motherboard was thinking that my CPU is overheating even at idle temp and locked the speed at 800MHz and was throttling it. Now it's back again performing as intended and the core speed is now stable at 4.0GHz all the time.

Thanks to everyone here who tried to help me. Greatly appreciate your time and help!
Best regards.

 

[SpecsGuy]

Are you sure your windows8 iso is completely ok? If there is an problem with windows setup files. It also can cause problems and it gets worse with updates. You may think windows installed properly but there might problem. If your files are ok i would say its an hardware issue.

I've tried many ways of installing the OS and ended up with the same results. It appears to me it's a hardware issue but I cannot tell which part(s) is responsible.

Also one more thing is that my PSU is 4-year old. It's been so many years and its switch (0/1) is stuck at "1" and does not turn off. However, it's been working good. So this could be suspicious too. I might end up changing the PSU too 'cause I'm getting sick of it.

My PSU is "Cooler Master i700 - 700W".

3 things are the most suspicious now in my list:
1) Motherboard
2) CPU
3) PSU

 

[Onus]

Well, the PSU is low quality, so I'd replace it anyway.

Have you tried a RAM test, one stick at a time?

 

[SpecsGuy]

Fixed the problem! I wanna thank everyone here for their time and effort trying to help me. I really really appreciate your help.

It was my motherboard. For some odd reason it was thinking that my CPU is overheating when even at idle temp. OMG, the 2 weeks of nightware are finally over. It was bottlenecking my CPU by decreasing its usage and core speed.

How I fixed it: I simply went to the BIOS and disabled an option called "Intel Adaptive Thermal Monitor" that stops the CPU from performing well when it's overheating.

Now its speed no longer gets locked at 800MHz. It's finally stable at 4.0GHz all the time. As for the cores usage reaching 100% without opening apps, I think that was a software bug in Win8.1. I thought that had something to do with the bottleneck but no, it does not. All YouTube vids show CPU cores usage that look similar to mine.

I contacted the MSI technical support and they told me to check if the CPU pins are bent (some had this problem with this same motherboard and their PC either won't boot or give errors while booting. However, I do not have these problems, luckily). They told me if not then request an RMA for the CPU and get a new one. I did not bother to do that and continued looking for a solution in the BIOS.


Again guys thank you SOOOO MUCH for trying to help me. Greatly appreciate your time and help.
Best regards.