I've flashed three of my HD5770's and all of them are working on 2.5 GT/s. There seems to be many people running these card as 5 GT/s.
I've seen this thread but it's seems to be scary: https://forums.macrumors.com/threads/1547340/
I was only able to get 5 GT/s by Crossfiring original Apple card with flashed one
I've seen this thread but it's seems to be scary: https://forums.macrumors.com/threads/1547340/
I was only able to get 5 GT/s by Crossfiring original Apple card with flashed one