Systems, apparatuses, and methods for performing efficient power management for a multi-node computing system are disclosed. A computing system including multiple nodes utilizes a non-uniform memory access (NUMA) architecture. A first node receives a broadcast probe from a second node. The first node spoofs a miss response for a powered down third node, which prevents the third node from waking up to respond to the broadcast probe. Prior to powering down, the third node flushed its probe filter and caches, and updated its system memory with the received dirty cache lines. The computing system includes a master node for storing interrupt priorities of the multiple cores in the computing system for arbitrated interrupts. The cores store indications of fixed interrupt identifiers for each core in the computing system. Arbitrated and fixed interrupts are handled by cores with point-to-point unicast messages, rather than broadcast messages.