Do a fresh installation of display drivers. Old graphics drivers leave traces that can mess things up with new cards unless you clean everything out using Display Driver Uninstaller (DDU). Here is the download link to the latest version of DDU:
http://www.guru3d.com/files-get/display-driver-uninstaller-download,14.html
It will start downloading automatically. Run it. Let it take you to Safe Mode by restarting the computer. When prompted, check the box to remove the C:\nvidia and C:\AMD folders. Use the option to clean and restart. That will put you back in Windows without any graphics drivers in addition to what Windows will use to display basic stuff.
Then - amusing you have an Nvidia card - download GeForce Experience from this link:
http://www.geforce.com/geforce-experience/download
Install it and open it. Under the "Drivers" tab, you can download the latest driver. Install it from there. If the windows doesn' fit on your screen because the resolution is messed up, click anywhere inside the GeForce Experience window to make sure it the active window, and then press on your keyboard "Window+Up Arrow." That will maximize the window and force it to fit on your screen so you can click on things.
After the new driver installs, restart - even if it doesn't require you to restart. You'll then be in Windows with new - and only new - graphics drivers.
If that doesn't work, then there is something more serious wrong, but be sure to try this first. It's a common issue when installing new graphics cards.