LAPTOP's connected to external displays do not work as expected
 

I've 2 laptops - a LENOVO and an MSI, both running on UBUNTU 9.10

both are connected to external displays.

LENOVO is connected to a 19" monitor connected through RGB. Although the monitor gets the output, I have not been able to turn the laptop screen off.

I ama trying to connect the MSI to an LCT TV. I can not get any output to the TV, although the TV senses that there is a signal comming from RGB port.

Does this have to do with UBUNTU config? Is there a way to get these to work?

THX in advance

What video cards to these laptops have?

MSI has the NVIDIA GeForce Go 6100
LENOVO has Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller

THX

Having the laptop display turn off when the external monitor is plugged in would be great. Making it permanent would be even better provided that it is smart enough to NOT turn off the laptop display when the external monitor is not plugged in.