Are Different Refresh Rates Handled Efficiently?

[Strill]

Say I have a 144hz monitor and a 60hz monitor. Is the game only sending the frames that each monitor needs, or is it creating 144 frames for the 60hz monitor, and throwing the rest away?

I ask because side monitors in multi-monitor setups are there mainly for peripheral vision, so I figure I could save some performance with lower framerates on the side monitors.

[Haldi]

AFAIK AMD and Nvidia render the FULL gameresolution in 144FPS and throw away these they can't use.

The only difference to this would be iRacing 2 as it's the first game which supports Multiple Viewpoints, so it might be possible to have 1 viewpoint at 144fps and the other 2 at 60 fps.... maybe... if the engine supports that.