iMac 2009 as monitor for Mini?

It can work, but only on the 27" iMac.

The '09 27" iMac accepts mini displayport input. Simply press CMD and F2 to switch screen between your iMac and other Mac. This is known as target display mode. Works great.

MatthewAMEL said:

That's what I have. The 27" iMac (Late 2009). Model A1312 or Mac 10,1.

So, which cable should I use from the Mini to the iMac? The Mini only has a HDMI output for video. All the adapters on the Apple Store say DP to HDMI. Does it matter which 'direction' the signal goes?

Click to expand...

As for HDMI out yes, it matters, and it's limited rez. Kanex makes (or made anyway) an expensive converter/scaler. The new Mac Mini also has Thunderbolt output. You would connect a Mini Displayport cable (NOT a Thunderbolt cable) from the Thunderbolt port to the MDP input/output on the back of the '09 iMac.

I'm 95% certain this is all correct since I researched this before deciding to stick with MDP about a year ago, until Thunderbolt becomes more prevalent and cross-compatible with other devices via converters...if that ever happens.

Apple provides free and excellent presales support via telephone or chat. Call to confirm. Bottom line is, you can feed a Displayport display with Thunderbolt output, but can't feed a Thunderbolt display with Displayport output.

MatthewAMEL said:

Thanks, I think I got it now.

Mini to iMac would work. iMac to Mini would not.

Click to expand...

The Mini isn't a display. The point is: Thunderbolt video output from a new Mac will feed an MDP input, which you have on the back of your 09 iMac. You could not however, for example, use the new Thunderbolt display as a second monitor for your iMac, which carries video output via the MDP.