Question Black screen after trying to install an old graphics card ?

[Nick17]

Hey guys I tried to install my old gt440 to maybe play some games ,I currently use Intel HD 630 graphics, So I tried to install it but I was not getting any thing so I removed it, problem is now I only get a black screen the pc turns on fine btw. What can I do now?
My system is
Intel g4600
ASUS H110M-D
8gbs of ram
Corsair Vs450 psu

 

[Nick17]

OK guys removed all the motherboards cable and reinstalled them because just removing the power cable monitor didn't work ,and now it works !What could have been the problem with my old gt card?