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This is required by the nvidia installer. This will kick off anyone who is logged in at the video console. So check to see if anyone is logged in at ":0" which is the video console. You can use the 'w' command for this. Here is an example of someone logged in at the video console:
[ksa@ksa-linux01 ~]$ w
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
ksa tty1 :0 Tue07 27:54m 0.00s 0.04s pam: gdm-password
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