Dear Friend
My PSU is a corsair 500w
Im have only motherboard, two units of rx470 , hd ssd , one fan of 120mm, Keyboard, mouse and monitor
***** ( im no have cd rom )
Thanks
Almir
My advice: try with a different PSU, but choose one with some more Amps on the +12V rail, like this:
See if you have the same issue.