The Radeon HD 5770 Mac Edition was a graphics card by ATI, launched in July 2010. Built on the 40 nm process, and based on the Juniper graphics processor,. RADEON HD 5770 1GB VIDEO CARD 639-0675 661-5718 Mac Pro 5,1 Original. Apple ， MPN: ： ： Chipset/GPU Model: ： ATI Radeon HD 5770.

I was being a dufus. It is a Mac Pro (mid 2010). For some reason it isn't letting me update the firmware using the normal shutdown, hold the power button until it flashes and emits a long tone. Without a firmware update I can't reload the High Sierra OS.I was going to just upgrade to Mojave to see if that was a work around but I have been digging through the tech files and my year of Mac and my graphics card are not compatible.It took awhile of digging before I found the answer, but I appreciate you trying to help. I was being a dufus.

It is a Mac Pro (mid 2010). For some reason it isn't letting me update the firmware using the normal shutdown, hold the power button until it flashes and emits a long tone. Without a firmware update I can't reload the High Sierra OS.I was going to just upgrade to Mojave to see if that was a work around but I have been digging through the tech files and my year of Mac and my graphics card are not compatible.It took awhile of digging before I found the answer, but I appreciate you trying to help. Apple Footer.This site contains user submitted content, comments and opinions and is for informational purposes only. Apple may provide or recommend responses as a possible solution based on the information provided; every potential issue may involve several factors not detailed in the conversations captured in an electronic forum and Apple can therefore provide no guarantee as to the efficacy of any proposed solutions on the community forums. Apple disclaims any and all liability for the acts, omissions and conduct of any third parties in connection with or related to your use of the site. All postings and use of the content on this site are subject to the.