HP Brio ba200 new power management for hp desktop pcs - Page 4

This illustration shows how the Hibernate mode works. Hibernate n System context saved to hard disk o All PC devices powered down The PC's system context (contents of main memory, position of all programs, etc.) is stored on hard disk and then all devices are powered off. The PC goes into state S4. When the PC gets a wakeup command, it initiates the BIOS then reloads the system context from the hard disk. In this way the PC starts up very quickly from where it left off, becoming quickly available for the task at hand. Wake Up from Hibernate n All PC devices powered on o System context recovered from hard disk The events that trigger the PC to wake up from Hibernate mode are: • Pressing the PC's power button (or the space bar on PCs that support this feature) • A scheduled event (such as a late-night backup) • A wakeup command from the network (typically, for desktop management tasks such as an automatic software upgrade) • An incoming call on a modem. Suspend to RAM Mode The new "Suspend to RAM" mode (S3) works in a similar fashion, except that the system context is saved to main memory. This state uses more power since the 4 main memory must be maintained to preserve the system context. However, since main memory is faster than the hard disk, wakeup takes less time from "Suspend to RAM" mode. The same events that trigger the PC to wake up from Hibernate mode also work for Suspend mode. Additionally, pressing any key on the PS/2 keyboard can also wake the PC up from Suspend to RAM mode (this keyboard wakeup can be disabled in the OS power management options). Under Windows 2000, ensure the OS option "Suspend to RAM" has been selected in Start>Settings>Control Panel>Power Options if you want to activate this mode. Which Operating Systems Support ACPI? Operating System Windows NT 4 Windows 95 Windows 98 Gold Windows 98 SE Windows 2000 Linux ACPI Mode Supported S1 S3 S4 S5 No integrated power management APM only APM recommended 9 9 8 9 9999 APM only Windows 2000 Windows 2000 is currently the operating system that has the most complete ACPI power management features. From the Windows Start menu, the user has the option to Shut Down (S5) or go into Hibernate mode (S4) if this is enabled in Power Management, or go into Standby (S3 or "Suspend to RAM"). Windows 2000 power management options are configurable from the Power Options icon in Start>Settings>Control Panel. Here you can set the action of the PC's power switch to instigate Standby (S1 or S3), Hibernate (S4), or shut down the PC (S5). You can also select the devices allowed to signal a wake-up to the system. The wake-up is carried out when an event is received from any of the devices you have set as 'active' in the Power Management tab of Device Manager (the Device Manager can be opened from Start>Settings>Control Panel>System>Device Manager).