Search results
Results from the WOW.Com Content Network
Idle is a state that a computer processor is in when it is not being used by any program. Every program or task that runs on a computer system occupies a certain amount of processing time on the CPU. If the CPU has completed all tasks it is idle. Modern processors use idle time to save power.
AMD Cool'n'Quiet is a CPU dynamic frequency scaling and power saving technology introduced by AMD with its Athlon XP processor line. [1] It works by reducing the processor's clock rate and voltage when the processor is idle.
In Windows NT operating systems, the System Idle Process contains one or more kernel threads which run when no other runnable thread can be scheduled on a CPU. In a multiprocessor system, there is one idle thread associated with each CPU core. For a system with hyperthreading enabled, there is an idle thread for each logical processor.
For example, hardware timers send interrupts to the CPU at regular intervals. Most operating systems execute a HLT instruction when there is no immediate work to be done, putting the processor into an idle state. In Windows NT, for example, this instruction is run in the "System Idle Process". On x86 processors, the opcode of HLT is 0xF4.
ACPI 1.0 (1996) defines a way for a CPU to go to idle "C states", but defines no frequency-scaling system.. ACPI 2.0 (2000) introduces a system of P states (power-performance states) that a processor can use to communicate its possible frequency–power settings to the OS.
CPU Idle: 0x05: Requests system suspend. 0) Clock halted until timer tick interrupt. 1) Slow clock [1] CPU Busy: 0x06: Driver tells system APM to restore clock speed of the CPU. Set Power State: 0x07: Set system or device into Suspend/Standby/Off state. Enable/Disable Power Management: 0x08: Restore APM BIOS Power-On Defaults: 0x09: Get Power ...
Timer coalescing is a computer system energy-saving technique that reduces central processing unit (CPU) power consumption by reducing the precision of software timers used for synchronization of process wake-ups, minimizing the number of times the CPU is forced to perform the relatively power-costly operation of entering and exiting idle states.
A finned air cooled heatsink with fan clipped onto a CPU, with a smaller passive heatsink without fan in the background A 3-fan heatsink mounted on a video card to maximize cooling efficiency of the GPU and surrounding components Commodore 128DCR computer's switch-mode power supply, with a user-installed 60 mm cooling fan.