Question is creating a custom display safe?

[zaydprovoker]

TL;DR:my monitor is 60hz at 1920x1080p and i wanted to create a new resolution to 1920x1080p but 75hz,my monitor is 75hz according to its website,it a viewsonic VX2453m-led

 

[rgd1101]

https://www.viewsonicglobal.com/public/products_download/68/20219.pdf?pass
page 15

 

[triplex1]

TL;DR:my monitor is 60hz at 1920x1080p and i wanted to create a new resolution to 1920x1080p but 75hz,my monitor is 75hz according to its website,it a viewsonic VX2453m-led

who is your gragic card