You said you plugged the wrong end of the PCIe cable, how come you don't see smoke coming out of the motherboard? Or you decide to leave that part out? When such happened to me in the past it ruined my motherboard and again motherboard isn't a stabilizer or something similar, they don't use fuse, I'm guessing the motherboard is toasted
no i think this didn't cause why would i hide anything my friend i did a mistake and i don't care what people things, we make mistakes and learn from it. The psu did not fire up so i think what i done is using the second psu to power the molex. in the handbook says use the same psu which is powering the motherboard should be powering the molex too. otherwise might cause damage which i think it did.
i never needed molex i thought it might give more stability but ashrock is rubbish making this update about molex is actually not needed for powered risers but everywhere on their website is saying plug the molex. I think it is an old board and they don't care about updating. They don't realise its probably the one of the most selling gpu in 2021. Big companies like this spending fortune for ads etc i wish they care about the support and updates for their product. At the end i got a new board now working fine with the same system and i will not use the molex on this one.