An X-ray detector system comprising a photon counting detector and a detector controller connected to said photon-counting detector, wherein said photon-counting detector comprises: a first subset of detector modules, wherein said first subset set of detector modules is a central subset of detector modules; and at least one second subset of detector modules, wherein said at least one second subset of detector modules is at least one peripheral subset of detector modules arranged on a respective side of said central subset along an axis of said photon-counting detector, wherein each detector module has power-consuming circuitry, and wherein: power-consuming circuitry of detector modules in said first subset, which is said central subset of detector modules, is configured, in an operational mode in which said detector modules are powered on, to consume a first amount of power; and power-consuming circuitry of detector modules in said at least one second subset, which is said at least one peripheral subset of detector modules, is configured, in said operational mode in which said detector modules are powered on, to consume a second amount of power that is lower than said first amount of power, and wherein said detector controller is configured to control said detector modules in said at least one second subset, which is said at least one peripheral subset of detector modules, to operate in the operational mode in which said detector modules are powered on, and in which said power-consuming circuitry of said detector modules in said at least one second subset is configured to consume said second amount of power that is lower than said first amount of power consumed by said power-consuming circuitry of said detector modules in said first subset, i.e. with reduced power. a first subset of detector modules, wherein said first subset set of detector modules is a central subset of detector modules; and at least one second subset of detector modules, wherein said at least one second subset of detector modules is at least one peripheral subset of detector modules arranged on a respective side of said central subset along an axis of said photon-counting detector, wherein each detector module has power-consuming circuitry, and wherein: power-consuming circuitry of detector modules in said first subset, which is said central subset of detector modules, is configured, in an operational mode in which said detector modules are powered on, to consume a first amount of power; and power-consuming circuitry of detector modules in said at least one second subset, which is said at least one peripheral subset of detector modules, is configured, in said operational mode in which said detector modules are powered on, to consume a second amount of power that is lower than said first amount of power, and wherein said detector controller is configured to control said detector modules in said at least one second subset, which is said at least one peripheral subset of detector modules, to operate in the operational mode in which said detector modules are powered on, and in which said power-consuming circuitry of said detector modules in said at least one second subset is configured to consume said second amount of power that is lower than said first amount of power consumed by said power-consuming circuitry of said detector modules in said first subset, i.e. with reduced power. power-consuming circuitry of detector modules in said first subset, which is said central subset of detector modules, is configured, in an operational mode in which said detector modules are powered on, to consume a first amount of power; and power-consuming circuitry of detector modules in said at least one second subset, which is said at least one peripheral subset of detector modules, is configured, in said operational mode in which said detector modules are powered on, to consume a second amount of power that is lower than said first amount of power, and wherein said detector controller is configured to control said detector modules in said at least one second subset, which is said at least one peripheral subset of detector modules, to operate in the operational mode in which said detector modules are powered on, and in which said power-consuming circuitry of said detector modules in said at least one second subset is configured to consume said second amount of power that is lower than said first amount of power consumed by said power-consuming circuitry of said detector modules in said first subset, i.e. with reduced power.