What does it mean to enable a feature?

A feature (one thing the chip can do, such as sleep) is enabled when every layer it needs turns it on, and it really works.

1. A list of power features
Each new chip comes with a list of power features: things it can do, such as speed up, nap or sleep.
2. Every layer must say yes
Most power features need several layers: chip hardware, the chip's own firmware, BIOS settings, and often the operating system (OS) and drivers. Like a lamp behind several switches, it stays dark if any needed switch is off.
3. Features arrive in stages
Early releases switch on only some features. Each new release of firmware, BIOS or drivers switches on more.
4. On is not the same as working
First ask: does the feature report that it is on? Then ask: does it really do its job, such as saving power?

Words to know

Feature: One thing the chip can do, such as saving power when idle.
Enable: Switch a feature on so that it can do its job.
Hardware: The physical chip and the board it sits on.
Firmware: Software built into the hardware that runs it from inside.
BIOS settings: Options in the BIOS, the start-up program, that turn features on or off.
Operating system (OS): The main software of a computer, such as Windows or Linux.
Driver: Software that lets the OS use one part of the hardware.
Release: A new numbered version of firmware, BIOS or drivers.

Early in a new chip's life, the team tracks which features each release switches on, and follows up on the ones that are missing or broken.

A feature says it is on, but the chip saves no power. Is it enabled?Think first, then tap to see the answer.

Not really. Enabled means it is on and it actually does its job.