Ok so my last judgment on this about Flash my Reference card for RX 580...
My card is a reference, purchased when got avaliable on the market here in Portugal... Stock Speed 1288Mhz/2000 ( Tuned by XFX )
http://xfxforce.com/en-us/products/amd-radeon-rx-400-series/rx480xxx-rx-480m8bfa6
I had this Sapphire bios ( 1411/2000 ) but few minutes ago changed for the XFX 580 unverifyed bios ( 1430 / 2000 )... Booted to the windows, but had to lower the clock. Because looks like my cards the Sweet Spot is 1400Mhz.. For some reason near 1420 ~1450 got some glitches on the image, no matter what voltage or power limit i add to it. The bios is the same as the
Gumby had up there.
Start fireStrike ( 1400 / 2100) and the first thing i noticed it was the clock throttling, so i pump up the Power Limit to +50 lol Surprise! 70c VRM max Temperature... So looking at my data before, +20 Power Limit on Sapphire bios had 91c ! And look at that Power Consuption xD it's so hungry now haha
My main problem comes at FireStrike Grafics Points, 14350 ???
http://www.3dmark.com/3dm/19445287?
Editing my original bios (RX 480) for 1400/2100 i got less a bit of power consuption and even more Grafics Points!
15k
http://www.3dmark.com/fs/12359610
So at least for me, i do not see any benefit on doing this... Sapphire Bios more VRM heat less Power Consuption more Firestrike Points, XFX bios a LOT power consuption less VRM heat less firestrike Points..
But can be all some bad readings from the sensors...
I will stick with my Rx 480 Moded bios xD Looks like... It was a good experience xD