144Hz refers to the refresh rate at which a Monitor or Display is capable of maintaining. In order to support the bandwith a 144Hz signal requires, the GPU needs a DVI output or DisplayPort output. However even at 1080p, the 560 Ti will likely have trouble maxing most games at 1080p and will require dropping settings to maintain 60 FPS in modern titles. To make use of higher refresh panels, you will need a card capable of maintaining >60 FPS to see the benefits over a standard 60Hz panel.
Hope this helps a little