I started to respond a couple of days ago, but I got sidetracked...
I do NOT know about your specific situation - Viewsonic in the dorm with a VGA patch cord laying around, et cetera - but I recently hooked up a Compaq lappy to my 42" Sony LCD.
The Sony manual said VGA will NOT work on my model. It supports s-video, composite, and (preferably) component input.
The Compaq only has VGA and s-video out, so the choice was obvious.
I connected the Compaq's ATI to the Sony through a s-video cable via the front 'game' panel on the Sony, plus a separate stereo audio cable for sound.
Then, I setup monitor 2 on the Compaq as TV out, and checked the box for extending the desktop unto it.
Nothing happened, so I rebooted the lappy, and boom! My desktop came up on the Sony.
Real Networks Premium (SuperPass) looks great on it, after doing a little fiddling with the colors and so forth. How about that Big Brother? 🙂
Windows itself is a little fuzzy, but let's face it, the built-in ATI chip wasn't designed to power a 42" screen, you know?
Anyway, that would be my suggestion - try s-video and see if you have any luck... 😉