i have new mobo, asrock h270 fatality performance. I cannot start more than one GPU. only main slot (16x with monitor) is working. bios not recognized other 3 card.
what can i do? it is very frustating...

i did updated bios. After update, i enable 4g decoding, also i saw to change speed ling to gen 1...and so on...nothing helped.
any idea?
Reinstall your windows in UEFI, not BIOS. Set mobo to default. Set your 4 cards. Enjoy.