There are at least 8 artists called "X".
These are photos from concerts where X played, so they may be of other bands that played the concert as well.
X Nov 3, 1983 Washington, D.C., United States Uploaded by Jeffrey Lee
Oingo Boingo / X Aug 20, 1983 Costa Mesa, California, United States Uploaded by Milocampo
X / D.O.A. / The Untouchables / The Flesheaters / The Hunting Game May 7, 1983 Sacramento, California, United States Uploaded by Sacramento Shows