Q: iMac 5k w/ Cinema Display 2nd Monitor Graphic Glitch

Hello,

I am currently using an iMac 5k w/ an Apple Cinema Display as my secondary monitor, when I move any window or click anywhere the screen seems to refresh and create graphical artifacts wherever the refresh occurs, see video for more details:

https://www.youtube.com/watch?v=4zRaZ7yKyLc

OSX Yosemite: 10.10.2

Model Name: iMac

Model Identifier: iMac15,1

Processor Name: Intel Core i7

Processor Speed: 4 GHz

SMC Version (system): 2.23f11

Serial Number (system): D2**********Y14

Hardware UUID: ***********

Any help would be appreciated!

Thank you.

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