I Want to install Mac OS on my Dell Optiplex 990

[Hammad]

Optiplex 990
Sys specs
CPU Core i5 2500
Ram 8 GB
GPU GTX 760
HDD 500 GB
I tried to install by open core method
I am facing an issue whenever I boot it gives me a blank screen after selecting Opencore Option

 

[OSX790]

What version are you trying to install?

Also the GPU will not work with the latest osx.