I did a fresh install of windows a couple days ago to see if it would fix the issue with the disable/enable. As for identifying a serial number what does that correspond to in the properties window of the gpu? I am on a H110 BTC+ motherboard.
You can actually hear the specific card cycle up when you re-enable. I encountered a similar issue due to different drivers for an older card already being installed. I did a clean sweep before reinstalling and it cleared up my 43 code.
The below link is a display Drive Uninstaller you might want to run. After you do that, try reinstalling the drivers. Good luck!
http://www.guru3d.com/files-details/display-driver-uninstaller-download.html