G0/S0/Working
On. The CPU is fully up and running; power conservation is on a per-device basis.
The Sleep States (Substats of G1 according to ACPI)
S1 Sleep aka suspend (computer wakes up faster but uses more power while sleeping)
Appears off. The CPU is stopped; RAM is refreshed; the system is running in a low power mode. No loss of cache
S2 Sleep to memory (computer wakes up slower but uses less power)
Appears off. The CPU has no power; RAM is refreshed; the system is in a lower power mode than S1. Disk cache is lost
S3 Sleep aka standby (consumes least power while sleeping. <20W according to energy star recommendations <10 W according to the recent EU recommendations. Remeber that news wherein suspending your computer was banned in Britain)
Appears off. The CPU has no power; RAM is in slow refresh; the power supply is in a reduced power mode. Disk cache is lost. Time taken to resume = time to power on monitor >/= S2
S4 Hibernate aka suspend to disk
aka Safe Sleep (Mac)
Appears off. The hardware is completely off, but system memory has been saved to disk.
However if you reset/remove the CMOS or change hardware, it may be possible that you cannot restore from your hiberfil.sys due to parameter mismatches.
You can however completely turn off your computer and UPS.
S5/Off
Off. The hardware is completely off, the operating system has shut down; nothing has been saved. Requires a complete reboot to return to the Working state.
S4 state does not use the BIOS switches and is totally controlled by plug and play operating systems like windows, mac and certain flavours of Linux.
G2= Soft power off i.e a normal shutdown
G3=Hard/Mechanical power state i.e. a power outage.
Totally off topic but did someone manage to get their hiberfile.sys off their boot partition and on a separate partition/flash disk?
I read it somewhere on xtremesystems a while ago that people use this approach in carputers (you guessed it right, a computer for your car) using flash disks.
i hate it when i have to keep the same space as the ram in the boot partition. I have configured my unattende windows setup to keep the program files and profiles folder on a separate partition and with no pagefile (winxp). This decreases fragmentation of the system files and increases performance. So any1 know a way. The only fragmentation of my boot partition (which i had to increase to 4 gigs from just 2gigs...was really fast) is due to my need for hibernation. (note, i know some people will point it out to me that the hiberfil.sys file space is always allocated and will not cause fragmentation, but i want the smallest boot partition without any problems in installing windows.
EDIT:
MSDN source
Code:
States S1, S2, S3, and S4 are the sleeping states. A system in one of these states is not performing any computational tasks and appears to be off. Unlike a system in the shutdown state (S5), however, a sleeping system retains memory state, either in the hardware or on disk. The operating system need not be rebooted to return the computer to the working state.
Some devices can wake the system from a sleeping state when certain events occur, such as an incoming call to a modem. In addition, on some computers, an external indicator tells the user that the system is merely sleeping.
With each successive sleep state, from S1 to S4, more of the computer is shut down. All ACPI-compliant computers shut off their processor clocks at S1 and lose system hardware context at S4 (unless a hibernate file is written before shutdown), as listed in the sections below. Details of the intermediate sleep states can vary depending on how the manufacturer has designed the machine. For example, on some machines certain chips on the motherboard might lose power at S3, while on others such chips retain power until S4. Furthermore, some devices might be able to wake the system only from S1 and not from deeper sleep states.
System Power State S1
System power state S1 is a sleeping state with the following characteristics:
Power consumptionLess consumption than in S0 and greater than in the other sleep states. Processor clock is off and bus clocks are stopped.Software resumptionControl restarts where it left off.Hardware latencyTypically no more than two seconds. System hardware contextAll context retained and maintained by hardware.
System Power State S2
System power state S2 is similar to S1 except that the CPU context and contents of the system cache are lost because the processor loses power. State S2 has the following characteristics:
Power consumptionLess consumption than in state S1 and greater than in S3. Processor is off. Bus clocks are stopped; some buses might lose power.Software resumptionAfter wake-up, control starts from the processor's reset vector.Hardware latencyTwo seconds or more; greater than or equal to the latency for S1.System hardware contextCPU context and system cache contents are lost.
System Power State S3
System power state S3 is a sleeping state with the following characteristics:
Power consumptionLess consumption than in state S2. Processor is off and some chips on the motherboard also might be off.Software resumptionAfter the wake-up event, control starts from the processor's reset vector.Hardware latencyAlmost indistinguishable from S2.System hardware contextOnly system memory is retained. CPU context, cache contents, and chipset context are lost.
System Power State S4
System power state S4, the hibernate state, is the lowest-powered sleeping state and has the longest wake-up latency. To reduce power consumption to a minimum, the hardware powers off all devices. Operating system context, however, is maintained in a hibernate file (an image of memory) that the system writes to disk before entering the S4 state. Upon restart, the loader reads this file and jumps to the system's previous, prehibernation location.
If a computer in state S1, S2, or S3 loses all AC or battery power, it loses system hardware context and therefore must reboot to return to S0. A computer in state S4, however, can restart from its previous location even after it loses battery or AC power because operating system context is retained in the hibernate file. A computer in the hibernate state uses no power (with the possible exception of trickle current).
State S4 has the following characteristics:
Power consumptionOff, except for trickle current to the power button and similar devices.Software resumptionSystem restarts from the saved hibernate file. If the hibernate file cannot be loaded, rebooting is required. Reconfiguring the hardware while the system is in the S4 state might result in changes that prevent the hibernate file from loading correctly.Hardware latencyLong and undefined. Only physical interaction returns the system to the working state. Such interaction might include the user pressing the ON switch or, if the appropriate hardware is present and wake-up is enabled, an incoming ring for the modem or activity on a LAN. The machine can also awaken from a resume timer if the hardware supports it. System hardware contextNone retained in hardware. The system writes an image of memory in the hibernate file before powering down. When the operating system is loaded, it reads this file and jumps to its previous location.
Which one draws more power standby or hibernate?
Re: Which one draws more power standby or hibernate?
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