Systems and methods are provided for powering an Information Handling System (IHS). The system includes a multimode AC adapter that reports supported outputs, including USB-PD (Universal Serial Bus Power Delivery) outputs and also including high-power outputs of a voltage greater than the USB-PD output voltages. The IHS detects a coupling of the multimode AC adapter to a USB-C port of the IHS. Based on information provided by the multimode adapter, the IHS determines the multimode adapter supports transmission of the high-power outputs to the USB-C port. The high-power outputs are negotiated and a power circuit of the IHS is configured for converting the negotiated high-power output. The configured power circuit converts the negotiated high-power output received via the USB-C port to an input utilized by the IHS. The high-power conversion circuit may provide efficient conversion of input voltages of up to 60 volts to voltages for use by the IHS.