I installed a new video card in my computer running Ubuntu 13.04. After rebooting I was greeted with a blank (black) screen. Bummer.
In my case, this was caused by the compiz and dconf files becoming corrupted in my home directory. How they became corrupted is unknown.
One quick way to determine whether your compiz and dconf files in your home directory have
become corrupted is to log into another user account on your computer and verify that a normal screen with the launcher/icons/notification areas are correctly displayed. This proved to be the accidental clue that I needed to figure out to solve my blank screen.
Should you have a blank (black) screen resulting from this issue, you can still use the terminal and other short-cut keys to access/launch programs.
Please note that the compiz and dconf files are "hidden" files.
In researching this issue, I ran across two websites that offered potential solutions should you be experiencing a blank (black) screen.
Reset Unity and Gnome to default values [duplicate]
How To Reset Compiz And Unity In Ubuntu 12.10 Or 13.04
Please be aware that having a blank screen may result from a variety of issues. This post is limited
to suggesting how to restore the compiz and deconf files to a default
state so that the launcher/icons/notification areas are restored.
Update: November 4, 2013. Updating to Ubuntu 13.10 resulted in a repeat of a blank (black) screen. This was resolved by swapping the non-working Nvidia graphic card with another. A less than optimal solution for now. Evidently, it seems that Ubuntu is "slow" in recognizing certain graphic cards (Nvidia) during boot-up. Ubuntu should have identified that proprietary Nvidia drivers were available, but did not. The replacement graphic card was also an Nvidia card, but was recognized during boot-up. So, if you are experiencing the blank (black) screen this may be another consideration.
Update: November 15, 2013. Well it appears that an associated, but unknown, Nvidia program may have caused the blank/black screen. The current Nvidia driver shown on another computer was 3.19. But for the problem computer it was still showing the Nvidia 3.04 driver. After aggressively removing all Nvidia programs, the computer video worked as expected and was updated to version 3.19.
Update: December 7, 2013. I ran across this post which attributes the blank (black) screen problem to nvidia-319-updates and nvidia-setting-319-updates. Once these programs were removed it appears that the problem was solved. Please review the full thread: After upgrading black screen and cannot use gui on ubuntu 13.10.