i think its a bug in the gpu-z program.
look here
http://www.geeks3d.com/20101110/radeon-hd-5550-rebranded-in-radeon-hd-6390-for-russian-market/
says here the 5550 and 6390 use the same id. maybe other cards do too.
maybe your card and the 5570 use the same id.
according to amd developer site...
i tried to oc this card, but whatever i changed the clock to it would set to 157 witch slowed down everything.. making lines on my screen when i moved windows around..
so i figured id flash the bois to fix it..
one thing i noticed about this card is for some reason the fan defaults to only...