This article is for Mac users only. If you are using another operating system, click HERE.   Some versions of Apple's MacBook Pro include two separate graphics cards, one weaker integrated card to preserve battery usage and one powerful dedicated graphics card for applications such as Vectorworks.

Depending upon which specific model of Mac you are using, you would control this in a different way:

For MacBook Pros (2010 - 2013) you would uncheck "Automatic Graphics Switching" as described here:   http://support.apple.com/kb/HT4110  
For MacBook Pros (2008 - 2009) you would select "Higher Performance" as described here, both in the Battery and Power Adapter tabs:   http://support.apple.com/kb/HT3207