Can I drive a second display off the 2009 27" iMac?

[NJRonbo]

Okay, so I have the 27" iMac that first appeared in 2009.

Know it has a display port in the rear.

Thinking of buying the 27" LED display and driving it off of
the iMac so that I have two monitors and I can easily move
windows and projects from one screen to the other.

Can this be done? Does the 2009 iMac support dual display?

If so, what will I need to accomplish this?

Thank you in advance

 

[simsaladimbamba]

Yes, it does support an external display, that is what the Mini DisplayPort is there for.
When you buy an Apple 27" LED monitor, just connect it via the built in cable (on the monitor) to the iMac.

If the display you buy has some other interface, there are adapters for that.

Mini DisplayPort (MDP)

Mini DisplayPort is the current digital standard on all current Macs to transfer video to an external display or TV. It has been introduced in 10/2008 with the release of the Unibody MacBook and MacBook Pros and has gradually been adopted on all other Macs.
MDP is capable of transmitting video, and since 2010, audio too. MDP is a miniaturised version of DisplayPort. It is also license free and can support resolutions of up to 2560 x 1600, which Mini DVI and Micro DVI are not able to do.

MDP adapters can be bought online from:

MDP to VGA adapter from Apple
MDP to DVI adapter from Apple
MDP to Dual-Link-DVI adapter from Apple

Moshi Mini DP to HDMI Adapter with Audio Support adapter from the Apple Online Store

Mini DisplayPort + USB to Dual-Link DVI adapter from Monoprice
Mini DisplayPort to DVI adapter from Monoprice
Mini DisplayPort to VGA adapter from Monoprice
Mini DisplayPort to HDMI adapter from Monoprice - *NOTE* This product will support audio on Mac computers capable of outputting audio through mini-displayport.
Mini DisplayPort to HDMI adapter from Monoprice - *NOTE* This product does NOT support audio for Macs that outputs audio through the Mini DisplayPort.
Mini Displayport Male and USB Male/Toslink Audio to HDMI Female Converting adapter from Monoprice
Mini Displayport Male and USB Male Audio to HDMI Female Converting adapter from Monoprice - *NOTE* Will only support 2 channel stereo. Will not support 5.1 Dolby Surround like the above adapter.

Mini DisplayPort to Mini DisplayPort Cables from Monoprice
Mini DisplayPort to VGA Cables from Monoprice
Mini DisplayPort to DVI Cables from Monoprice
Mini DisplayPort to HDMI Cables from Monoprice​

Also of interest: "What is "Mini DisplayPort"? Is it an industry-standard? How is it different from or better than Mini-DVI and Micro-DVI?"
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