https://bugs.freedesktop.org/show_bug.cgi?id=93652
--- Comment #20 from Marek Olšák maraeo@gmail.com --- I've never seen any hangs with Fiji (Fury) and it's my main development card.
There is a VBIOS switch on the side of the card. When the computer is powered off, flip the switch to the other position. See: http://www.legitreviews.com/wp-content/uploads/2015/07/sapphire-fury-switch....
The picture shows the "best performance" position. (also higher power consumption) Hawaii (290, 390) has the switch too.
I have the switch in the same position as on the picture. It's known to be the only stable position for my 290, and it's the only position I tested with my Fiji.
Remember to flip it when the computer is powered off.