Have the same issue with one laptop, 100 cpu but no processes using it. I know my issue, it’s the goop needs to be replaced between the heat sync and the CPU. I know it sounds strange, but it took me forever to find this resolution.

I once tried to pull the heat sink off a CPU and the CPU came out of the motherboard. No way was I getting that to go back in.

https://www.sevenforums.com and http://www.tomshardware.com are good forums.
There are also probably better ones out there.

I was having the same problem but it turned out to be a MSSE bug running the CPU and fan at 100%.
Reinstalled and then eventually switched to Malwarebytes and the roses are shiny again.

(Well not perfectly shiny. A process called com.surrogate still tends to corrupt my thumbnails and slow down clicks. Plus an occasional BSOD to let me know who is boss. And KB4343900 is a frigid tease sent to destroy humanity.)

Do a start->run->msconfig and uncheck/kill all startup programs like Outlook Skype or anything that doesn't need to be running in the background all the time even when not in use.
Services.MSC is another important line command used to fix things.
(That is where my pay grade ends)

There are also bitcoin viruses going around which use your computer energy to 'mine'.
Spybot or others will probably get those.
Also clean up temp file with CCleaner and defrag overnight with something quality.

I read through your posts again and did not see you mention the brand of computer nor did I see a post listing the "users" logged into your computer nor "system", "network" or other system level users that start processes and many times there will be 3 copies of the same thing running, one for you, one for system and maybe one for network?

Do you have to log into the network to do whatever it is you do? You didn't mention what your job is and how it connects to everything else? If it is a HP, those folks load several background processes that want to connect to HP everyday for updates and if they cannot get through, everything slows down and stops. Similar to processes having to go into a network server to get data or updates or ????? and if all 3000 users are banging away sharing porn or whatever then your PC will be at the end of the line. It will take a bit of effort but look to see those running processes and services are connecting to and are they doing anything requiring network access?

I agree with killing services and processes until CPU usage drops to < 5% or so or the PC is killed. Please let us know what is happening.

It wasn't a process that was using all of the cpu, it was probably one of the services.
I'd kind of wondered if a reboot would do the trick, but I'm definitely not surprised that a reboot and some updates fixed the glitch. The folks in the company that push the updates probably pushed a bad one that caused the issue, then either rolled it back or pushed a new one to fix the old one.

Meh, that's BS. I've got a bunch of Apple stuff, phone, tablet, TV, and my wife has an Apple laptop. My next PC will be a MAC. My current PC is at least 8 years old and running Win 7. Years ago, I upgraded from Windows 7 Home to Windows 7 Premium. My PC is still humming along nicely. I've been waiting for it to die, so I can get a MAC, but it won't die or slow down or start acting weird/wonky. THere's absolutely NOTHING wrong with Windows.

It's also much, MUCH easier for Apple since their OS is basically running on locked down hardware.

I rarely use task manager anymore. I use Resource Monitor. If you go to the performance tab in task manager, there is a button at the bottom you can click on to get to Resource Monitor. I have a icon I click on in a side bar. RM will show a lot more processes than TM. Much more detail in general.

Note that Windows does their regular updates on the second Tuesday of the month, which can get carried over for a day or two.

Having memory usage maxed out can cause problems because the system will need to do a lot of paging, I had this problem until I increased my memory to 8G, which I see you already have.

Locked out by IT unfortunately.

Dell, engineering application. Always connected to the mothership. I should have mentioned that...a lot of things are outside my control. Including virus scans at odd times of the day.

Well in that case I would lean on your "IT Professionals" to find and fix he issue since you can't work!

Amazed what people are willing to put up with to avoid going Linux or Mac.

8 years with my current Mac PowerBook. Zero issues.

Easiest fix is save your personal data and reformat the hardrive. Then reinstall windows 7.
Mechanical hard drives are all slow compared to solid state drives which are at least 4 times faster because there are no moving parts and all the flash memory cells are powered up and can quickly read or write data at any time.

Windows 7 Ultimate or Pro is by far my favorite operating system. Win7 Ultimate has everything Microsoft ever made for windows 7 in it or it's downloadable from MS.
I hate Windows 8 or 8.1 and it's charms bar, but the annoying charms bar can be calmed down in the task bar properties dialog box menu.
Window 8 or 8.1 is semi tolerable with the Classic Shell windows 7 start menu installed and running in it after the awful charms bar is modified and shut off as much as possible.
Only good thing about windows 8 or8.1 is it can be updated to windows 10 for free if you saved the install files back when MS was giving it away for free 2 or 3 years ago.

Windows 10 is almost as bad as 8 but at least it comes with a start menu.
There is no privacy in Windows 10 unless you are disconnected from the internet and Microsofts servers. That said, Jetboost and Spybot Anti Beacon will help turn off Windows 10 user telemetry with Microsoft until the next windows 10 update turns it back on... and you can not turn off windows update in windows 10 unless you know how to do that in services, you can only defer it for a very short while.

Another nice thing about windows 7 is you can completely turn off windows update in windows update settings if you want to.
There is a program out there called remove wat which will remove windows activation technologies from windows 7.

Windows 10 compatibility mode for old XP progams is garbage and does not work at all for some programs.
Windows 7 compatibility mode for old windows XP programs works really well in my experience.

I still install Classic Shell in Windows 10 Pro and set it for the Windows 7 start menu because I'm used to it and like it better. With classic shell installed in 10 you can easily switch back and forth from the windows 10 start menu with it's tile screen to the windows 7 style start menu.

With Windows 10 home or Pro it's like you never own the operating system and Microsoft just lets you use it because you will never have full control of it as long as you are connected to the internet while the microsoft servers are monitoring your operating system and in control of it... If you don't believe me just try installing KMSPICO and see how long it takes for windows 10 to remove it.
I do know what I am talking about and I know more about windows than some professional IT guys I have met or know.

I don't like MAC either but it is a good workstation operating system for graphic designers, photographers, and artists.
MAC is color managed, can display the full Adobe RGB color space, and has a larger color Gamut then Windows because of it. Windows can only display the smaller srgb color space
For most people that makes no difference but Graphic designers and Art directors want to use the larger color managed Adobe RGB color space for good reason.

Sixty years ago a wag once said of the Lotus 40, " it's just a Lotus 30 with 10 more mistakes." Suffered with Windows 10 for the last two years.

Macs are wonderful if you do graphics, or standard Microsoft Office tasks, and surf the net. If you get into real power usage, you need a Windows based or at least UNIX based system. I have several programs that together are more than I paid for my first Porsche, and we get to do that each year. The all specify Win 10 Pro, with lost of RAM. I end up building a custom computer from components to meet our needs.

I love my iPhone 6S. We were at the Mac store and I got a new batteries for my wife's and my phone. As we picked them up they had us stand next to the most powerful computer they sell. It was not very impressive. Low RAM, and not even a top CPU. The price was impressive.

The ability to add multiple NVIDIA 1080 TI cards in one system is important for the 3D programs we run. I fully understand we are not the average user.

I know what you mean, I have the same experience with my current HP all-in-one running Windows 7. And I've installed, uninstalled and reinstalled probably hundreds of shareware/freeware apps in that time.

As an IT guy dealing with software updates, security and patching for very large companies, I will add that MS new patching model and quality assurance thereof has been complete crap since Win10. Every new release of W10 breaks tried and true methods of doing specific work or presents problems for vendors, and every patch tuesday is a complete crapshoot... Also MS tries to sneak updates of the OS on you every chance they get.

I don't love what Apple is doing with OSx (ipadizing the Mac, and constantly nagging you re:updates you can only defer for a day) but I have nothing but macs at home because I don't wanna work on computers on my free time. Win7 was the last decent Win OS in my book but it's out of support very soon... (which is hindsight could be a great thing! no more $hite patches, take your chances with vulnerabilities instead of bluescreening with "fixes" ;-)

Back in the day when I was managing the users and their computers at COMNAVAIRPAC in San Diego we had issues with illegal software, patches, virus programs and other things that were a huge headache. When we had about 700 users, some (finance) had 3 or 4 "special" computers that connected to servers in various places in D.C. and PA. It took me a year or so to convince the Admiral and the chief of staff that we had to be legal, up to date and using only approved software. We handled patches and updates with loading them onto a small "test LAN" to see what would happen and also test programs that someone would want use for special needs. A person who would not "play by the rules" had to explain to the chief of staff why they were special.., didn't work most of the time!