Typically not. I have seen a few laptops that have a add on card that is the video card and you could change it. But you would have to get it from the OEM.
My Computer
At a glance
Windows 7 Enterprise (x64); Windows Server 20...16GB
Computer type
PC/Desktop
Computer Manufacturer/Model Number
Dell OP7010
OS
Windows 7 Enterprise (x64); Windows Server 2008 R2 (x64)
the price for a new laptop video card is extortionate , if it is an addon card you may be able to get a cheaper ATI mobility card , if its soldered to the board then , im afraid, you're stuck with what you've got