hello i have 2 xfx r9 290 not unlockable and one asus matrix r9 290x on my system. In dx12, crossfire is enabled but time spy in 3d mark only uses the first card the asus one. If i test tomb raider with dx12 enabled only the first card works, but in dx11 all of them work, and in fire strike 3d mark again again all of them work. I think this is a problem with dx12 crossfire with different device ids in cards. I tryied to write bios from r9 290x to my 2 xfx cards, but ati flash changes device id from 67B1(290) TO 67B0(290X) but when i use gpu z in windows the device id is not changed it is still 67B1, SO NO LUCK WITH XFX cards, My second option is to try to change device id to the matrix card, can someone please if this a correct idea mod my bios from device id 67B0 to 67B1 so i can test the other option?
here is my bios