[SOLVED] Stuttering in almost all games on a high-end PC. Need serious help.

[CNPressley]

This is an issue I have been dealing with for quite some time, nearly two years. My PC has been having stuttering issues on essentially all of the games I play despite having very high FPS. No matter what I do, I cannot seem to find the solution to my problem, not even upgrading my specs made any difference.
My specs (whatever has "upgraded" means I've replaced trying to fix my problem):
2080ti
i9-9900k
Gigabyte Auros Ultra mobo (upgraded)
Corsair Vengeance 16gb ddr4 3200mhz Ram (upgraded)
Samsung EVO 970 NVME (upgraded)
EVGA Supernova 750 PSU (upgraded)
Acer Predator G sync display
It is safe to say that with these specs I should not be having any issues. Here are some examples of the stuttering issues I get:
Witcher 3 - Stutters when first entering novigrad or other populated areas, however once I enter once it no longer stutters until the next time I play
RDR2 - Will have no issues until around 45 minutes of playtime, then I get constant stutters in Saint Denis whenever I move around
BF5 - will stutter when I first load in and engage in battles, but after a few minutes it no longer stutters until the next time I play
American Truck Sim - Stutters randomly as I drive into new areas
Mordhau - Sometimes a random stutter a match, but few and far between
There are probably more instances I am forgetting as well. As you can tell it is very strange and I have no earthly idea as to how to pinpoint the problem.
Here are all of the things I've tried to do to fix it (if I forgot something I will add it when I remember):
Upgraded almost all of my hardware
DDU graphics driver uninstaller
Reinstalled Windows countless times
Updated to Windows 2004
Turned XMP on and off
Every variation of Vsync on/off in both control panel and in-game
Every variation of Gsync on/off with and without Vsync
I've tried messing with BIOS settings
Turned "game mode" on and off
Tried games in fullscreen and windowed
Tried different outlets around the house and different surge protectors
Made sure all of me temps are fine through MSI Afterburner (which they are)
Used Rivatuner to limit my FPS
Used Standy Cleaner or whatever that app is that clears standby memory
Used Memtest to make sure my Ram is good (which it is)
Changed my graphics settings as low as possible (which I shouldn't have to do) and it still persisted
Turned Windows Defender on/off.
Turned off all in game displays (Nvidia, discord, etc)
Again there are probably plenty more things I have tried, however nothing seems to ever change my performance. At this point I am at a loss and have spent more time on this computer trying to troubleshoot than actually enjoying my time gaming. If there is anyone out there who has managed to fix this obscure problem, I would really appreciate the help.

 

[Ralston18]

Observe system performance using either Task Manager or Resource Monitor. Use both but just one at a time.

Observe while the system idles, while you do light work or browsing, and lastly while gaming.

Determine what resources are being used, to what extent (%) the resource is being used, and what is using the resource.

Drives: make, model, capacity, how full?

Check Task Manager Startup - there may be applications being launched that originally were not there.

 

[tomitomi]

I had a similar problem like yours 2 years ago...after tons and tons of things that I've tried, I finally found the solution. In Bios, the RAID was selected instead of AHCI. I never expected that to fix it, but it did.