—Many data center devices, for instance packet switches, can be modeled within the context of resource constrained queueing systems. In this paper, we define a novel algorithm class which simultaneously addresses three significant concerns in the operation of such systems: stability, differentiated QOS, and power control. This class, which we refer to as target/power projective cone scheduling (TP-PCS), encapsulates many previously studied algorithms as special cases. At the same time, however, it is broad enough to include a rich set of other, potentially superior control procedures. In the first part of our paper, we explain our model as well as some previously studied approaches to scheduling in these systems. We then define TP-PCS, show how it relates to the former algorithms, and discuss how members of this class can be tailored to control for both power and QOS. Finally, we test some instances of TP-PCS on a simulated, input-queued switch. These show that a wide variety of ...