Although the iMac computer comes with a screen that tops out at 27 inches, some users may want a more enhanced viewing experience by connecting the iMac to a high-definition television (HDTV). Connecting your iMac to your TV also allows you to stream videos from the computer's Internet connection so that you can watch the Internet content on your TV.
Set up your iMac so that it is positioned next to or nearby your TV. Plug in your iMac so that it is powered and check to make sure that the Internet connection is working.
Look on the back or side of your TV to see what type of connection it requires from your iMac. Video Graphics Array (VGA) connectors are often labelled PC and have the appearance of an inverted trapezoid consisting of 15 holes divided into three equal rows. If your TV does not have a VGA input, it most likely has either DVI-D (Digital Visual Interface in digital mode), which is a rectangular connector with 24 small squares with three rows. Alternatively, your TV may also have an HDMI (High-Definition Multimedia Interface) connection, which is a trapezoidal shape with small pinholes on the top and bottom of the inside of the trapezoid.
Attach a mini display port to DVI or mini display port to VGA to your iMac, depending on the input connections on your TV. Attach a second cable connecting the VGA from the cable connected to the iMac to the VGA connection on the TV. If you are not using a VGA connection on your TV, utilise the appropriate cable to connect the iMac's mini display port output to your TV. The mini display port connection is located on the bottom left corner of the back side of the computer.
Connect an audio line out (3.5 millimetre cable) to the TV's audio line in.
Click on the "Apple" in the top left portion of the iMac's screen and select "System Preferences." Click on the "Displays" option and click on "Mirror Display." Choose the resolution that is appropriate for your TV.
Test the installation process by switching your TV to its auxiliary input mode and begin streaming videos from your iMac.
Using an HDMI connection, which is standard on most new HDTVs, will give you the best picture quality when transferring images and streaming videos from the iMac to the TV. Older iMacs may have a mini DVI port which can be connected to VGA, DVI or HDMI depending on your TV's configurations.
Standard definition TVs will most likely have a lower resolution than the monitor on your computer, causing some distortion in the picture quality. The resolution specifications for iMacs are 1920 by 1080 pixels for the 21-1/2-inch screen and 2560 by 1440 pixels for the 27-inch screen.