1340 MHz core and 2150 MHz memory clock is way too much for a RX 570. Try setting 1200 Mhz for the core clock and 2000 MHz for the memory.
I dont really see how that would help as they crash on stock speeds but i will give it a go
So now they just crash instantly compared to original clocks. Have I messed up my cards or just my bios?
Have checked risers they are all good unless my bios messup destroyd them
What Bios mod have you done with the cards that are crashing?