Methods and apparatuses for dynamically budgeting power usage in a data processing system. In one aspect, a data processing system, includes: one or more components including a first component; and a computing element, such as a microprocessor or a microcontroller, coupled to the first component to obtain one or more operating signals from the first component and to determine, based at least in part on the one or more operating signals, an estimate of a power consumption requirement of the one or more components for operating under the current condition. In one example, one or more sensors are used to determine information on actual power usage for a past period of time. A performance level setting of a second component, such as a CPU, a GPU, or a bus, is determined using the estimate and the information on the actual power usage, such as the operating voltage and frequency.