AMD Radeon HD 5770 supported for Mojave?

Apple does not support that card. And unmodified Mojave will not install when that is the only card present.

There is a hobbyist hack that will allow it to install using that card, and it works OK, but there are a few graphics anomalies. You would probably not be able to edit videos, but you can play internet videos fine.

It appears that the firmware update for High Sierra is mostly to get APSF boot support, and a rumored additional firmware update for Mojave did not happen to me, so I assume if you do one or the other you are done with firmware updates.

there might be a fix

These are great computers. There IS a fix. Your graphics card is not too tired to perform ordinary tasks quite well -- other things must be at fault.

Download and run this little "discovery" Utility and it will generate a report. You don't need to buy anything unless you want to. When it has completed, "Share" and it will put a sanitized version of the report on the System Clipboard, and you can Paste the whole thing into a reply on the forums with one Paste command.

User Tip: Using Etrecheck

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