Why would my non dual monitor setup revert to dual monitor

[ITPaladin]

I just reinstalled my scsi zip and cdrw combo to try and see if it still worked.

When I restarted, I received the scsi card bios screen (woot!). Both monitors turned on during the boot sequence, and then my LCD became the default on the login screen.
I had my CRT as the main monitor and did not have spanning on before. I had the LCD off before shut down.

I found this was an odd thing so I was wondering why did it do that?

 

[Peter]

You probably just didn't notice before, because the boot phase went much faster without the SCSI chain enabled. During boot, Windows settings obviously aren't relevant yet. In this early stage, all the usual graphics cards BIOSes turn on whatever displays they detect.

 

[ITPaladin]

no. I had the LCD off, and when I got to Windows, both monitors were on.