Would it be a problem even if its the same PSU? Because I was going to use that other PSU to power on some of the GPUs. Besides that, it still doesn't turn on. Even if I just use one PSU.
One problem at a time mate, one problem at a time, fix the motherboard to power on first before worrying about using two power supplies on the motherboard, if the motherboard is up and running then we can talk about how to use two power supplies