MSFS (nor other games) utilizing my 2070super

Out of nowhere, MSFS (and American truck sim as I found out trying to troubleshoot) are not detecting nor using the 2070 super on my desktop machine.

I noticed it when the frames halved and all of a sudden I can't get more than 15.  When I enabled the dev mode FPS, the problem is glaring.

It seems as though my 2070 super card is "stuck in neutral" as when I look at the MSI Afterburner app monitoring performance, it never "kicks in" when the app is launched, meaning that it usually spools up and temps start to rise as the GPU is being used. Nope, it just sits there, temp at 54, fans completely idle.
...even tried other intensive gaming apps, same thing...horrible performance.

After fiddling with a few hours last night, I got "something" to work, as in the FPS shot way back up and all was in the green...so I "thought" I fixed it, mainly by doing the common steps to fix these kinda things.
Went to bed, and today, same thing. 

I have the nvidia activity monitor on, and the funny thing is when MSFS launches, it displays on the list...but ONLY until you get to the copyright page (after the Blackshrk AI intro)....once it starts loading the app, MSFS drops off the list of apps using the 2070 (or which there are 17 at the moment so its not like its not working)

Updated drivers, rolled them back, latest Win 10 updates installed, yadda yadda, all no effect.

and the weird thing is...it is now exhibiting a behavior I've never seen....the GPU line in the FPS window cycles super fast between 11 and 64 ms....creating this interesting pattern on the GPU rail...this happens when its MSFS is loading up to the point of ready to play, then it falls to steady 64ms:

All while the temp sits at 54 with MSFS running. Like it's trying to start the GPU but fails and fails.

I am completely stumped on this one.  Pulled the card, cleaned it even though there was zero dust, cleaned minor dust from the case, everything else is great...oh, and Photoshop seems to use the 2070 just fine and stays on the list, as does Chrome and many other apps.

Desperately need some help.

Specs if they help

Asus ROG Hero MB, up to date
32 gb ram
EVGA 2070 super
750 Corsair PSW 
Use HWM to watch temps and volts, GPU is at just about idle and even under heavy load never gets above 80c, MB/CPU cores also cool...zero overclocking on any component.

Edited July 16, 20214 yr by Steve Dra
added context