Hi,
might as well do my introduction with a proper post.

So I got an XFX 7970 Gigahertz edition, double dissipation. non-reference board with two dvi, hdmi and two dp ports. No bios switch too.

The sticker on the board says: 797G-TD  FX-797G-TDF VA1
GHZ DD RADEON XT2 1050M WITH BOOST

Atiflash product name: Tahiti B0 XT2 C38620 GDDR5 3GB 500e/150m
BIOS P/N: 113-797TDF70-101
BIOS ver: 015.022.000.001.000000
BIOS date: 07/18/12

No matter how I configure cgminer I can only get ~520kh/s out of the card.

Reading around, it seems a different BIOS would help, so I tried a bunch with crappy results.
None of the XFX ones will even boot, gigabyte won't load drivers, sapphire will load drivers but crashes. All were different 7970 BIOSes.
I tried one xfx r9 280x but that one wouldn't even flash for some reason (flashing failed).

I welcome any suggestion as to what BIOS might work for this card.