Question No display to monitor after reinstalling old hardware

[Jake Snow]

I discovered I needed a boot kit for my new hardware and ordered it. In the meantime I was going to put my old hardware back into the computer and use it until the boot kit comes but now my display won’t show up when I turn on the pc.
I have tested the monitor and it works fine with other devices
I inspected the gpu and it seems to have no physical damage as well as the pci slot I used. Everything in the computer worked fine before this so I know for a fact it is compatible
Any help would be greatly appreciated

 

[Jake Snow]

I discovered I needed a boot kit for my new hardware and ordered it. In the meantime I was going to put my old hardware back into the computer and use it until the boot kit comes but now my display won’t show up when I turn on the pc.
I have tested the monitor and it works fine with other devices
I inspected the gpu and it seems to have no physical damage as well as the pci slot I used. Everything in the computer worked fine before this so I know for a fact it is compatible
Any help would be greatly appreciated

Also for viewer’s information I’m new to pc building and maintenance so I could have missed something simple