All of our EVGA power supplies are manufactured to conform to ATX standards. The ATX specification has different ratings for voltage and wattage, depending on the connector that is used. In a typical configuration, where a graphics card is directly installed into a PCIe slot on a motherboard, that PCIe slot is specified to deliver 75 watts.
PCIe risers and adapters do not conform to ATX standards. Using these types of adapters can result in damage to any system components.
The ATX standard for SATA or Molex connections is rated for 54 watts. Each SATA/Molex connector provides three 12v pins at 1.5 amps each, for a total of 4.5 amps. 12 volts, times 4.5 amps, equals 54 watts able to be provided by a SATA/Molex connector.
Some PCIe risers do not conform to ATX specifications. As ATX specifications require the PCIe slot to supply 75 watts, a PCIe riser may potentially overdraw the SATA/Molex connector by 21 watts. Please confirm that any risers you use meet ATX specifications before use. Risers that do not meet ATX specifications are not recommended for use with any EVGA power supplies or graphics cards.
If multiple graphics cards are needed to be installed in a system, it is recommended that they are installed directly into the PCIe slot on the motherboard.