Question Can i set up two sapphire rx 570s in a cross fire

[Roger Har Dang]

so far i've tried everything but i guess they're still not in a crossfire , when i open up the crimson driver , it says "discreet" which i assume means they are not yet a crossfire ? also one is in pci 3 x16 but the other is pci 2 x 4 ! is that a CPU limitation ? can you help me with this please

 

[HEXiT]

that bord wont run crossfire the x4 slot will cripple performance of the second card
the second pci-e slot is only really for nand/flash drives and such... not a gpu...

 

[Roger Har Dang]

my board is a x399 asus . in its specifications says it supports crossfire ? what board do you recommend for a crossfire ? is there a board you can install 4 amd cards , instead of 2 ?