A green check with a plus sign means it is supported and recommended. This is the one you will want. There may be multiples for your card use the one that is the highest version with the green check/plus.
The Revit list page does not have the ability to download the driver. So you have two choices, you can download it from the graphic card manufacturers website or you may be able to find it on the Autodesk website under the AutoCAD drivers and download it from there.
To download it (if available) from the Autodesk AutoCAD graphics driver website run the query at: http://www.autodesk.com/autocad-graphicscard
In the list of drivers, click the blue down-arrow next to the driver version you need and select the save option to download it to your hard drive.
Note: this is the list for AutoCAD based programs, so you should only download and install the version listed as supported/recommended from the Revit list.
Always use a supported/recommended driver and a certified card whenever possible.
The National Support Center is here to help you with your software issues and we can be reached at 800-808-7645.