Question high cpu usage until i open task manager

[lingarajug]

new build and as title states, cpu utilized approximately 40-50% at idle and once i open task manager i can see the utilization high but before i can see or task manager figures out whats going on and cpu usage quickly drops to 5-9% and i cant see what was causing it as it changes so quickly and all i see is 0% for the top listed apps but cpu usage high, i have performed windows defender offline scan, malwarebytes scan, mcafee and stinger scan whcih did not find anything and i am out of ideas what to do next, any help appreciated.

 

[rgd1101]

new build, new os install? do another fresh os install

 

[lingarajug]

@rgd1101 thank you and its a new build and new install of windows 10 1909 (18363.476), i have downloaded almost 300-400gb of various pc and vr games and they are all on C drive and it took me a week to set everything up and i dont have the patience to go all over again, i am mostly positive its not a virus or any other similar but something in windows itself, tried various methods of fixes that i found on various forums but none applied to my case or help fix it, i just want some help in diagnosing and fixing this issue apart from fresh OS install, thank you once again.