Molex or Floppy?
Computer power supplies normally have extra connectors in case you ever need to upgrade your computer.
In order to deliver enough power to a USB 3.0 PCI and PCIe card you will need to plug in a spare power connector from your computer power supply. Some USB 3.0 PCI and PCIe cards require a Molex power connector or a floppy power connector.
No spare power connector on your computer power supply?
A Molex power splitter plugs into one that is already in use and splits the connection into two.
No floppy power connector on your computer power supply?
You can use this convertor to change the Molex connector to a 4 pin floppy power connector.
Does your computer power supply only have sata power connectors?
You can use this converter to change the Sata connector to a Molex connector.