If you have video display but cannot select the video resolution that you want:

• Check the resolution specifications for the monitor to make sure that it is capable of displaying the desired resolution (on this site, see Products, select by monitor size, select monitor model number, scroll down to Resolution specifications). 
• Make sure that your computer or video card supports the desired resolution (see documentation for your computer or video card)
• Make sure that the drivers for your computer or video card are up to date (consult the computer or video card manufacturer's Web site)