A data processing system characterized by: a high-performance computing subsystem having a first processor, a low-performance computing subsystem having a second processor independent from said first processor and said low-performance computing subsystem having lower power consumption and lower computing performance than said high-performance computing subsystem, and a controller coupled to said high-performance computing subsystem and to said low-performance computing subsystem; said low-performance computing subsystem: (i) being configured to be controlled by said controller, and (ii) being configured to: boot in an initial step from off to power-on, while keeping said high-performance computing sub-system powered-off, and enter a low-power waiting state, enter upon an inactivity timeout a standby state; return upon a wake-up event to said low-power waiting state; and (iii) being configured to control said data processing system to act as a single computing device by moving software execution to one of: said high-performance computing subsystem when high computing performance is needed by booting said high-performance computing subsystem (230, 235) into a booted state, transferring control of user interface means to said high-performance computing subsystem and running said software (245, 250, 255, 260), or said low-performance computing subsystem when low computing performance is sufficient, by transferring control of user interface means to said low-performance computing sub-system, and stopping said software (270, 275); and if said low computing performance is sufficient, to put said high-performance computing subsystem into a power saving mode, thereby arriving at said low-power waiting state (280, 285, 220). a high-performance computing subsystem having a first processor, a low-performance computing subsystem having a second processor independent from said first processor and said low-performance computing subsystem having lower power consumption and lower computing performance than said high-performance computing subsystem, and a controller coupled to said high-performance computing subsystem and to said low-performance computing subsystem; said low-performance computing subsystem: (i) being configured to be controlled by said controller, and (ii) being configured to: boot in an initial step from off to power-on, while keeping said high-performance computing sub-system powered-off, and enter a low-power waiting state, enter upon an inactivity timeout a standby state; return upon a wake-up event to said low-power waiting state; and (iii) being configured to control said data processing system to act as a single computing device by moving software execution to one of: said high-performance computing subsystem when high computing performance is needed by booting said high-performance computing subsystem (230, 235) into a booted state, transferring control of user interface means to said high-performance computing subsystem and running said software (245, 250, 255, 260), or said low-performance computing subsystem when low computing performance is sufficient, by transferring control of user interface means to said low-performance computing sub-system, and stopping said software (270, 275); and if said low computing performance is sufficient, to put said high-performance computing subsystem into a power saving mode, thereby arriving at said low-power waiting state (280, 285, 220). (i) being configured to be controlled by said controller, and (ii) being configured to: boot in an initial step from off to power-on, while keeping said high-performance computing sub-system powered-off, and enter a low-power waiting state, enter upon an inactivity timeout a standby state; return upon a wake-up event to said low-power waiting state; and boot in an initial step from off to power-on, while keeping said high-performance computing sub-system powered-off, and enter a low-power waiting state, enter upon an inactivity timeout a standby state; return upon a wake-up event to said low-power waiting state; and (iii) being configured to control said data processing system to act as a single computing device by moving software execution to one of: said high-performance computing subsystem when high computing performance is needed by booting said high-performance computing subsystem (230, 235) into a booted state, transferring control of user interface means to said high-performance computing subsystem and running said software (245, 250, 255, 260), or said low-performance computing subsystem when low computing performance is sufficient, by transferring control of user interface means to said low-performance computing sub-system, and stopping said software (270, 275); and if said low computing performance is sufficient, to put said high-performance computing subsystem into a power saving mode, thereby arriving at said low-power waiting state (280, 285, 220). said high-performance computing subsystem when high computing performance is needed by booting said high-performance computing subsystem (230, 235) into a booted state, transferring control of user interface means to said high-performance computing subsystem and running said software (245, 250, 255, 260), or said low-performance computing subsystem when low computing performance is sufficient, by transferring control of user interface means to said low-performance computing sub-system, and stopping said software (270, 275); and if said low computing performance is sufficient, to put said high-performance computing subsystem into a power saving mode, thereby arriving at said low-power waiting state (280, 285, 220).