1440p 144Hz
Radeon RX 5700 XT
For 1440p at 144hz, your best options are probably in the used market in the form of a 1070TI or Vega 56/64. If you prefer to buy new (and remember that a used GPU will perform EXACTLY the same as if you bought it new), then my recommendation would be the Radeon RX 5700 XT. Performance wise the RTX 2070 SUPER seems to beat the XT more often than not (usually by very small margins), but it costs too much for what it offers ($100 more than the XT). If both were at price parity, my recommendation would the RTX 2070 SUPER, but for now the 2070S continues NVidia’s trend of overpricing their GPUs by excessive amounts. A shame really.
Buy on Amazon