144hz or above cheapest g sync monitor

You did not mention size or resolution, warranty, etc... So. if you want cheap as in price, then scrolling through eBay would be the place to look as in used.

Like WildCard states, G-Sync is not a "cheap" option. It usually adds on average an additional $200 to a monitor, that would otherwise be a standard 144Hz or Freesync version.
 


It’s not 1440p and I’m pretty sure and 10y0 on medium can run most games over 100