never use more than 3 sata / molex from same strand of PSU then problem sorted, cause when you use 4 and ambient go hot +25° psu connector can fire.
3 on sata? were not 2001 anymore, its 2 sata 3 molex.
i just had 1 sata to molex melt on a single line with nothing else coming off it , and the riser was only running a single UNDERvolted 460 50w draw on psu