Used this to make up for the lack of PCIe slots on my cheap $15 secondary PSU. The maximum power you can get is 132W at 4 pins (11A at 12V pins), which is enough for most graphics cards when you turn on the 75W that the PCIe slot itself provides. This product now has two 4-pin Molex connectors, so if your power supply has two 4-pin Molex connector bars, you can theoretically provide 2 x 132W with this adapter.