What does G-Sync exactly do on a monitor?

[Fir3dog]

So whats the difference between a monitor with G-Sync and one without it?

 

[Spectre694]

G-sync/Freesync tie the monitor refresh rate to the refresh rate of the GPU. Basically instead of the monitor working at 60Hz all the time while the GPU is outputting at 48-65FPS(Hz) the monitor runs at 48Hz when the GPU outs 48 FPS or 60Hz at 60FPS or whatever it is.

 

[beegmouse]

Google it.

 

[Fir3dog]

What does it benefit if the monitors Hz match the GPUs framerate like does it take up less power or take up less performance cause I don't see how for example if you are playing at 45 fps and you have a 60hz monitor what is benefitting if it matches the fps? I'm confused of what the point of it is exactly.

 

[Spectre694]

What does it benefit if the monitors Hz match the GPUs framerate like does it take up less power or take up less performance cause I don't see how for example if you are playing at 45 fps and you have a 60hz monitor what is benefitting if it matches the fps? I'm confused of what the point of it is exactly.

Simplest way to explain is V-sync in reverse. instead of forcing the card to output at the monitors refresh it just matches the monitor to what the card can do. Makes it look a little smoother on FPS drops and helps prevent screen tearing and the like.

 

[beegmouse]

It uses more power if anything.

If your GPU can output 60, 61, 61.2685,65fps 9(any value within a range) thats what the monitor will display. So where as a good GPU would work at 80% playing a game locked at 60fps/60Hz.
A a G-sync/Freesync monitor will use 100% and output at 75fps (60fps/80%)
But the situation is dynamic, not fixed. In one second there may be 75frames, in the next 72 and so on.
The GPU works at 100%, no frames are torn and no frames are dumped.