Hi everyone I bought 3 Sapphire RX560 Pulse OC boards,
I only managed in one of them to work 100% to bios @Priviet
the other 2 Sapphire RX560 Pulse OC none of the available bios @newsector and @Priviet give color screen after a few minutes. 
RX560 Pulse OC 6 pin standard is almost 12mh/s I do not understand, the boards are the identical why only in one of them took round for days to almost 15mh/s @Priviet and the others give the color screen.
I was looking to buy other RX560 Pulse OC 6 pin but now I do not know what I do.
I only managed in one of them to work 100% to bios @Priviet
the other 2 Sapphire RX560 Pulse OC none of the available bios @newsector and @Priviet give color screen after a few minutes. RX560 Pulse OC 6 pin standard is almost 12mh/s I do not understand, the boards are the identical why only in one of them took round for days to almost 15mh/s @Priviet and the others give the color screen.
I was looking to buy other RX560 Pulse OC 6 pin but now I do not know what I do.
Are you sure all 3 use same memory?
According to GPU-Z Memory Type (Micron) of the 3 only 1 of them I can use memory clock in 2140MHz
Status https://prnt.sc/fvj833 The three are Micron type.Strange that in the other 2 if I put of 1750MHz for 2000 or until 1850MHz in 10 minutes it locks
the screen turns black sometimes it stays of another colors. 
The 3 pieces came together sealed and new, strange the other 2 just pick up with the original Bios or by being at 1750MHz.
How do you flash the bios ? provide the used command
I record the normal flash I believe https://prnt.sc/fvqdo1
or
1. cmd as administrator ---> cd C:\atiflash_274
2. atiwinflash -unlockrom 1
3. atiwinflash -p -f 1 bios2200max-2100def-1750atallabove.rom (0 for first and 1 for second)