One of the internet sources has posted pictures on whole series of XFX 6800 graphic cards.
According to pics below, there are total of six models, three for HD 6850 and the same for HD 6870.
As wee see, it is basically the cooling system which makes difference to models. Other specifications remain the same.
Cards are expected to have dual slot cooling system of reference AMD design, dual-slot cooling system of XFX design (with two fans) and even single-slot cooling system of XFX design. The last is possible only for HD 6850 cards.
XFX pays great attention to cooling system by giving lots od details of its own design card coolers and comparing with one of AMD reference design.
Next is the picture of HD 6850 card’s PCB showing cards dimension.
The power subsytem is 4-phased, three for GPU and one for memory. Additional power is drawn through one PCI-e 6-pin connector. The TDP of this card is less than 150W.