Replacing monitors running Vista Premium

I installed Vista Premium on a new system. Original monitor was an analog LCD connected through an adaptor on a dual DVI graphics card. Everything was fine. All drivers updated; all downloads completed. Then I swapped the analog for a digital LCD monitor. Vista refused to boot. No warnings; no error screens - just refused to boot. All I got was a DOS screen usually associated with an F8 reboot: Safe Mode. Last Known Good, Start Normally, etc. No choice worked. Put the analog monitor back on - BINGO. Vista starts as if nothing happened. I asked MS about this through their Vista Communtity forum. An MS rep said that because lcd panels are fixed pixel technology, I should boot to safe mode and confirm my resolution, etc. He ignored the part where I said no boot was possible; and "fixed pixel technology"? A fact to be sure, but he's blaming the monitor! Replacing monitors does not effect XP like this. Am I off base, or was I given a technical bs brushoff? Isn't this a Vista snafu?