I am the person that will be helping you today.
May I ask for the brand and model name of the video card?
I will be standing by.
May I ask into which slot you are putting the video card?
No, I was just awaiting your return. May I start a remote screen sharing session with you so that I can better help you resolve this problem? When the remote begins, a chat window will appear that we can use to communicate with each other.
The card should be recognized. In such cases, the culprit is more often than not, the power supply. Did you install a new power supply with more power or are you using the stock power supply?
It is difficult to say how the power supply would effect the system in such cases. Is the card known to be good and working?
As long as you don't have it disabled in the BIOS/CMOS, it should be working. If you have another card you can test, you can do that. Please, test the card in another computer and verify that it is indeed, working. I will be standing by. Thank you.