I am setting up a brand new Win 10 computer following what I have learned on Bleeping Computer and Microsoft Support. I worked for about 20 hours on a long list of settings and program installations, and all went well until at a certain point both Windows and web browsing slowed down markedly. A recent restart with updates took 45 minutes.
Unfortunately I failed to keep detailed notes so I don't recall at which step the problem appeared, nor did I set restore points during the process. Now Task Manager Performance moving graph shows CPU hovers at about 60% when the computer is at rest, with nothing open other than Task Manager. If I clik on any icon, CPU instantly plateaus at 100%. Looking under Task Manager Processes, I see almost all processes stay at 0% CPU with brief jumps to no more than 5%. A few AVG processes hover at less than 5%. There are only two standouts: Windows Audio Device Graph Isolation hovers at about 17% and System Interrupts at about 15%.
By comparison, my old Windows 7 computer at rest with many programs open shows 0% to 5% CPU Usage.
A partial list of the setup steps I took includes:
Malwarebytes, AVG, Ccleaner, SuperAntiSpyware, Spybot, ADW Cleaner, Panda USB Vaccine, VLC Media Player, Firefox, Sumatra PDF, Secunia PSI, Wiz Mouse, Dropbox, setup an Admin account and a limited account for daily use and browsing, turned off autoplay, ran Windows update, Wifi hotspots off, show file extensions on, adjusted for best performance, turned off Win 10 Tips Tricks and Suggestions.
I have Googled problems with the two processes above, but the results look complicated. I would be very grateful for any help with this problem so that I don't have to re-install Win 10 and start all over.