Examples described herein relate to a device that includes: a first power rail to provide a signal from a power source to a reference supply voltage pin of a memory controller; a second power rail to provide a signal from the power source to an output buffer pin of the memory controller and to an output buffer pin of a central processing unit (CPU). In some examples, the second power rail is separate from the first power rail, during a high power state, the power source is to supply a same voltage to each of the reference supply voltage pin, the output buffer pin of the memory controller, and the output buffer pin of the CPU, and during a connected standby state, the power source is to reduce voltage provided to the output buffer pin of the memory controller and the output buffer pin of the CPU using the second power rail and maintain a voltage provided to the reference supply voltage pin.