Interesting observation at IronGeek on using hooking a Dell XPS L502X laptop to a VGA beamer:
After doing some playing around, I figured out it would not connect to a monitor or projector that did not send EDID or DDC2 info.
Lesson learned: if you run a Windows 7 laptop other than a Mac, and the laptop has a Mini DisplayPort adapter (like a Dell XPS L502X) and want it to connect to a VGA monitor, then get the StarTech model MDP2VGA adapter. It just always works, whereas a Mac Mini DisplayPort to VGA adapter won’t work on systems not providing EDID or DDC2 info.
–jeroen
via Mini-DisplayPort on New Dells: Resolving issues with output to projectors in Windows 7.
The Wiert Corner - irregular stream of stuff 