MacBook has problems with external monitor but iMac doesn't
Not all monitors are the same - I bought a monitor from a friend to use for extra screen space space with my 13"MBP (Mid 2009). It was a nice VGA widescreen LCD monitor but no matter what I tried my MacBook Pro could not send any kind of signal to it. All connectors were verified to work perfectly well and the monitor also worked perfectly well when attached to a nearby PC...