[CentOS] Why is my default DISPLAY suddenly :3.0?

I'm on Fedora 6.3. After a reboot, some proprietary software didn't want 
to run. I found out that the startup script for said software manually 
sets DISPLAY to :0.0, which I know is not a good idea, and I can fix.

However, this still doesn't explain why my default X DISPLAY is suddenly 
:3.0.

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Joakim Ziegler  -  Supervisor de postproducción  -  Terminal
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