One of my users has a Dell Latitude D620. She has had no issues with it to speak of. She recently re-docked the laptop as she has countless other times and now it won't recognize the external monitor's native resolution of 1280x1024.
Same monitor, same laptop, same software, but it's 'forgotten' the external resolution of 1280x1024 and now maxes out at 1024x768.
I have had this happen with another user who also has a D620, both have the Intel 945GM graphics chipset, and we never really got his fixed either.
Of course Dell hasn't updated their driver for this in over a year, despite Intel having released an update this February (which I don't think will install due to the OEM blocking, but I'll find out later today for sure).