Good news ! (Sort of...)
I rebooted and edited the boot command of my kernel in grub, using e... and
then booted it.
I added the following to the command line: rd.driver.blacklist=nouveau
modprobe.blacklist=nouveau nvidia-drm.modeset=1
This caused the kernel to boot with nvidia instead of nouveau. Even
better, the nvidia driver decreased my CPU load tremendously in the
application that I was working with. From 90% (barely useable) to 30%
(loafing along).
Now I just need to figure out what is going on with my boot setup.
Thanks for all the help!