Using an iMac as an External Display

[CNSabers]

Hello,

I recently purchased an iMac Retina 5k to replace a mid-2011 27" model that was having speed problems. I would like to use the old Mac as an external display using Thunderbolt. I have a few questions about this.
First, do I need RAM in the computer that will be used as an external display? Ideally, I would be able to move the 2 x 4GB modules that I have into the new computer. Second, will the old iMac being used as an external display be doing any computing itself, or will it just display what the new Mac tells it to?

Thanks for your help,
Connor

 

[old-wiz]

The computer acting as external display has to be running osx, which means you need ram and a bootable device (ssd or hdd).

 

[UniDoubleU]

Hello,

I recently purchased an iMac Retina 5k to replace a mid-2011 27" model that was having speed problems. I would like to use the old Mac as an external display using Thunderbolt. I have a few questions about this.
First, do I need RAM in the computer that will be used as an external display? Ideally, I would be able to move the 2 x 4GB modules that I have into the new computer. Second, will the old iMac being used as an external display be doing any computing itself, or will it just display what the new Mac tells it to?

Thanks for your help,
Connor

The ram from your iMac 2011 probably wouldn't work with iMac 5K though as it's specifications are different. The iMac 5K uses DDR3L 1600 NB Ram, really important to be low voltage.

You'll need a Thunderbolt cable. Here for more info.

http://support.apple.com/en-us/HT3924