Didn't the cards come with instructions on driver install?
Also, some machines may require more steps to get drivers working. As there are so many PCs today I can't be specific. But what you wrote sounds like a driver issue.
This is why many just take it to the shop. No one can see your PC, OS, BIOS settings and even then there's only a slim chance you'll get a step by step. Many guides on changing video cards out there. Here's one.
http://www.tomshardware.com/answers/id-1823362/uninstall-graphics-card-driver-putting.html
I'm new to the forums and am here with quite a strange problem. Might not be to you, but for me, it's quite strange.
I'm currently running windows 10. My "old" graphics card is the GeForce 9800 Gtx+ and it stopped working with my 1tb hard drive.
The issue: When turning on the computer with the graphics card enabled, the window's logo will appear with the loading circle, flash, turn on the second monitor, and remain in the black screen without ever continuing.
After giving up, I decided to retire the old graphic card and purchase a Nevidia 750ti series graphic card in hope to fix and play games more efficiently.
The issue: The previous problem happens again.
Now here is where I get lost : When the graphic's card is enabled with the 1TB hard drive, I have the black screen error. But when I plug in my old 150GB hard drive, the new and old graphic's card works like a charm. Did I instal something that messed up my adapters setting on the 1TB? Do I need to erase all data on the 1TB and start all over? Do I need to purchase another hard drive? What are your solutions/suggestions. Thank you.

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