I’ve had this problem for a while and made no progress trying to troubleshoot it myself, although I had a workaround. Now, with the latest 352.21 driver, my workaround no longer works.
Here are the details: (will attach nvidia-bug-report.log.gz too)
1x EVGA GTX 980 Superclocked edition
1x ASRock X99 Extreme11 motherboard
1x Samsung 27" S27D590C monitor (connected via displayport) - center display, landscape mode
2x Dell U2412M 24" monitors (1 connected via displayport, 1 via DVI) - left and right displays, portrait mode
OS: Fedora 21 Linux, kernel 4.0.8-200.fc21
Nvidia driver: 352.21 (installed via RPM from rpmfusion yum repo)
When I have all monitors attached and running at their native resolutions (Samsung=1920x1080,Dell=1920x1200), the nvidia-settings utility’s “PowerMizer” shows it is running at performance level 3. And indeed, the temperature of the card is hotter than usual.
When I only have the Samsung display connected, the PowerMizer perf level goes to 1 when it’s relatively idle and goes up when I run graphics intensive applications or games. I think this is normal. But, with the two Dell monitors attached in a 3-display setup, the perf level is stuck on 3 and the card gets warmer even with little graphics compute power in use.
Previously, with 346.47 version of Nvidia driver, I was able to workaround this problem if I set the resolution of the Dell monitors to 1920x1080 instead of it’s native 1920x1200. This would at least not cause my GTX 980 to waste energy when idle.
However, after updating to the recent 352.21 version, the workaround no longer works. My PowerMizer performance level is constantly stuck at level 3 and the card is running 15-20C hotter than normal.
Can anyone please help? I’m happy to provide more information if I missed anything.
nvidia-bug-report.log.gz (78 KB)