The ATI Radeon HD 5770 video cards are supported only on Mac Pro (Mid 2010) models. They are not supported in earlier versions of Mac Pro. Learn more about graphics card compatibility for Mac Pro.
Mac Pro: Using ATI Radeon HD 5770 graphics card with Mac Pro released before 2010
You may notice display anomalies or issues playing back video or other HDCP-encoded content when you use an ATI Radeon HD 5770 video card in Mac Pro computers released before the Mac Pro (Mid 2010).
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