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AMD captures 28.7% market share in desktops
(www.techpowerup.com)
This is a most excellent place for technology news and articles.
I'd drop in an old Nvidia GPU for transcoding, anyway. There's lots of old cards that support nvenc. Don't neglect the Quadro cards, either. Lots of them are cheap on ebay and will transcode just fine without even needing their own cooling fan.