Update my graphics card and get a new 120-144hz monitor or just get a G-Sync monitor only?

[truc]

I play my games at 60fps with a GTX 650Ti Boost using adaptive sync with my 60-75hz monitor. Does it make sense to upgrade my graphics card to push more fps and get a new 120-144hz monitor? Or should I just invest in a G-Sync monitor only? What matters to me is reducing lag input.

 

[4K POTATO]

personally i would say to upgrade yourGPU first if anything, unless you see problems with you monitor 60-75hz is fine.