Fedora 27 [GeForce GTX 650] [Driver 390.25] High CPU usage

[This may or may not be the same as https://devtalk.nvidia.com/default/topic/1030209/linux/fedora-27-geforce-gtx-750-ti-rev-a2-driver-390-25-high-cpu-usage/ ]

After updates to 390.25 (from RPMFusion) my system became essentially unresponsive.
On a 4-core, 8-hyperthread processor, top(1) said that gnome-shell was taking around 750% of the CPU.

I first reported this in the RPMFusion User list and that thread has useful information. Here’s the list archive. Unfortunately, the thread has not shown up.
https://lists.rpmfusion.org/archives/list/rpmfusion-users@lists.rpmfusion.org/

In particular, Nicolas Chauvet thinks that the problem is with the EDID of my monitor. He said:

"The root cause seems to be because of your monitor, as the edid
considered as invalid by the nvidia driver.
But the driver constantly tries to revalidate the edid.

It’s possible that there are others errors, but nvidia guys would know"

My monitor is s Seiki SE39UY04 TV set. It is UltraHD at 30 Hz. My GTX 650 + Fedora + nvidia driver have driven it well for 3.5 years.

When I downgraded the driver, my system worked again.

I have a nvidia-bug-report.log.gz but don’t know how to attach it to this message. Maybe I’ll be prompted when I submit this.
nvidia-bug-report.log.gz (172 KB)