New 27" iMac 2012 external monitor

How do you mean this? Ive got a 2009 imac with a 24" cinema display attached..

No..you can't do this...

You could with the 2009-10 ones using displayport, but not the 2011-12 unless the source supports thunderbolt output (Basically just other modern Macs or very modern thunderbolt equipped PCs - which are rare). There was a lot of talk about hdmi>thunderbolt adapters coming out but I think it became apparent that high cost and conversion lag would make such a product practically unsellable.

The 2009 and 2010 27" models could do it with the Kanex HDMI to Mini-Displayport input adapter.

The 2011 and 2012 models can only act as a display to a computer with Thunderbolt video output, which at the moment basically means other 2011 and newer Macs (ie hook up a 2011 or 2012 Macbook Air to a 2011 or 2012 iMac).

There are some PC motherboards / expansion cards that do Thunderbolt video out but I haven't seen any tests that show those working with the 2012 iMac.

I asked Apple support and they told me as long as the PC motherboard has a thunderbolt connection, the iMac should work as an external display for a Windows PC. There are several motherboards available with thunderbolt connection.

EDIT: They are wrong. It doesn't work. Only with the thunderbolt display.

Mac32 said:

I asked Apple support and they told me as long as the PC motherboard has a thunderbolt connection, the iMac should work as an external display for a Windows PC. There are several motherboards available with thunderbolt connection.

Click to expand...

You'll have to dig into the forum, but I remember reading at least one post of a guy who bought a specific motherboard just for this purpose and it didn't work.

Really? Strange that it works with an Apple Thunderbolt Display (I've seen it on youtube), but not with an iMac. Maybe he used a display port connection from the PC to a thunderbolt iMac?

You need a motherboard that support Lucid Virtu MVP (like ASUS P8Z77-V), so that you can get the signal from the discreet graphics card through the motherboard thunderbolt connection. It is explained below:

http://www.youtube.com/watch?feature=player_embedded&v=O1t7Rc9qFgI#!