In all likelihood, you won't be able to upgrade the graphics card in a laptop, unless if it's in MXM (Mobile PCI Express) format. But even then, because MXM isn't a standard among all the laptop makers, MXM cards are expensive, rare, and often won't be compatible with your laptop even IF you have the right MXM slot for an upgrade.
mruffin75 refers to the Asus C90, which was built with upgradeability in mind.