At the bottom of the graphics settings page, there is an option to turn off VSync.  Does anybody know what this does?

VSync synchronizes your games FPS to your monitors refresh rate. I always have it turned off so I can get above 60 FPS, however this is not always desirable. 

VSync synchronizes your games FPS to your monitors refresh rate. I always have it turned off so I can get above 60 FPS, however this is not always desirable. 

Would you recommend it being turned off?  

Yes, turn it off, I read it also speeds up the loading.

Would you recommend it being turned off?  

 

It's a compromise both ways.

If you turn it on, you could get some mouse (movement) issues.

If you turn it off, you could (& most probably will, with GTA) get screen tearing.

If your FPS is usually under 50-60, then it's better to turn it off, so as not to give more load on the PC (although the load is very very little, but in some games it gives a noticeable improvement).

 

People like turning it off so they get "higher FPS", doesn't really matter, since their monitor is displaying 60 FPS anyway (& it's not changeable [it's physically locked to it]. Unless you're using a [for example] 120Hz TV as your monitor, then it's [physically locked to] 120FPS).