I managed to make them work together. The problem was I moded Rx570 bios so reseting it to stock bios fixed the problem. However stock setting is around 22MH/s for Ethereum  doesnt even worth power consumption.
Anytime I mod the bios for better starps Windows doesnt recognize it.

I used the blockchain driver. what did u exactly do ? I installed vega first then tried 570 first. i tried both on pcie 16 on mobo. no luck.


which version of windows 10 u using ? Im using windows 10 fall creators update.

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After installing the driver try to use AMD/ATI Pixel Clock Patcher https://www.monitortests.com/forum/Thread-AMD-ATI-Pixel-Clock-Patcher
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Used that too. no difference.

Thank u all for ur help:)

guys is there a way to mix install these cards ? i tried blockchain drivers. recent non chain drivers. even older 16.11 drivers.
Rx vega 56 is installed correctly and windows recognize rx 570 but there is a yellow triangle on it. I used update driver and it says there is problem installing the driver correctly.

i used ddu in safe mode to remove drivers.
Anyone tried this mix install ? Any success ?