Back in the OS9 and older days, you had to select the display you wanted to use, and if it didn't work, you did a PRAM reset to get it to work. Maybe you need to try this.
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MacBook 2GHz Intel Core 2 Duo w/ 2GB DDR2 RAM & 120GB SATA 5400RPM HDD
Canon Rebel XTI
Google Cr-48 Beta Laptop