Laptop computers are harder to install components in than the desktop equivalents. A graphics card can be installed in a Toshiba laptop, but
you need to completely disassemble the laptop. The graphics card is located under the motherboard; therefore you need to remove most of the laptop components to access the card. Be sure to touch any non-painted metal that is connected to ground to avoid harming your computer with an electrostatic discharge.
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Yes some cards available for notebook pc, but I am not confirm about their cost and availability.
Visit this http://www.villagetronic.com/vidock2/index.html
As I have seen your configuration of your laptop it is not good for high end games. But you can use/ try this if you want to upgrade this one.