The card may just need thoroughly cleaned/blown out with canned air..Or
disassembled and the TIM replaced, using only a BB-sized drop of TIM in the center of the GPU chip.
And/or:
If the card won't throttle down/runs hot due to the dual displays, you could grab
NVIDIA Inspector and right-click on
Show Overclocking and then
Multi Display Power Saver..Select the
Target GPU, then set the
Activate Full 3D by GPU Usage - Threshold to, say, 40% and see if it helps.
You could also try running
Display Driver Uninstaller in Safe Mode to uninstall the Graphics Driver and optional driver components..Then install the latest NVIDIA Driver using the Custom (Advanced) option and select to install only PhysX along with the Graphics Driver..The other optional driver components can be installed at any time.
Just a few things here.