BOOT CAMP 272 (22/04/03)

PC Power Management, part 2

If you managed to wade through last week’s acronym-laden introduction to Windows PC power management you may have concluded that the whole thing is a bit of a mess, and you wouldn’t be far wrong!

It can be a nightmare for novices and even some expert users give up and just let their computers get on with it, which is a pity because the concept is basically sound. Millions of idling PCs around the world waste a huge amount of energy and money, not to mention the contribution they make to global pollution.

Configuring your PC to reduce its power consumption when it is not being used is not that difficult and need only take a few minutes. It will almost certainly save you money -- probably not a lot but every little helps. It can also reduce wear and tear and prolong the lives of some components but before we get started a word of warning. If your PC has had power management problems in the past and is now behaving itself, you might want to leave well alone or confine yourself to fine-tuning the settings. In any case note down any changes that you make, so you can undo them if your PC starts playing up or refuses to shut down properly.

For the sake of simplicity we’re only going to be looking at desktop PCs using Windows 98 SE onwards. Laptops generally have their own convoluted power management systems for prolonging battery-running times; older machines using earlier versions of Windows may support power management but it can be patchy or unreliable. PCs more than six or seven years old do not usually have ATX-type power supplies, which prevents them going into suspend or sleep modes. If you are using Windows 95 or your PC has a front-panel on/off power switch rather than a push-to start power button then this article is likely to be of relatively little use to you.

Before you can use your PC’s power management systems they have to be properly enabled in the BIOS (Basic Input Output System) program. It’s surprising how often manufacturers forget to do this. The BIOS is responsible for testing and configuring your computer when it is powered up and before Windows loads. On most PCs the BIOS is accessed by pressing the ‘Del’ key, (or a combination of keys) as soon as it is switched on, consult your PC’s operating manual for more details. BIOS menus vary but most have a Power Management section and usually the first option is to enable or disable the two most commonly used power saving schemes: APM (Advanced Power Management) and ACPI (Advanced Configuration and Power Interface). Both should be enabled though on some PCs only APM may be available. Touch nothing else, save the setting, exit and allow the PC to boot up to Windows.

Most of your PC’s power saving facilities can be accessed from Control Panel (Start > Settings in Windows 98/SE/ME or on the Start menu in XP), click the Power Management or Power Options icon and select the Power Schemes tab. You can also get to the same settings by right clicking into an empty area of the desktop, select Properties then the Screensaver tab. You should see the Energy Star logo, indicating that your monitor’s power saving facilities have been recognised by Windows. Click the Settings or Power (in XP) button to take you to the Power Management control panel.

Here you will find the basic controls for setting what your PC does when it is not being used. Under Power Schemes check that your PC type has been correctly selected, in Windows 9x the choices are normally between Always On, Home Office/Desk and Portable/Laptop. Windows XP may have a couple of extra options for specialist PCs or applications but in general you should stick with Home Office/Desk.

Below that you’ll see the delay times for powering off the monitor and hard discs, the defaults of 15 and 30 minutes, which suits most people but don’t be afraid to experiment if they don’t fit your pattern of working or you leave your desk frequently. Depending on the number of power management features available on your PC you may also have an options to set delay times for ‘System Standby’ and System Hibernation’. This is where the really big power savings can be made, especially if you leave your PC on all day or overnight. Standby puts the machine into a kind of semi-comatose state with monitor and disc drives powered down but it will wake up and be ready to use when a key is pressed or the mouse is moved.

If the period of inactivity continues the PC goes into Hibernation mode, which is the lowest power state aside from switching it off completely. The PC saves the information in its memory, details of open programs and the data showing on the screen etc. to a file on the hard disc. To wake it up again it’s usually necessary to press the power button, the PC goes through its BIOS checks but then goes straight to where you left off.

If your PC is capable of hibernation there will be a Hibernation tab in Power Management, (make sure the option is checked) and it will appear as on the shutdown menu on the Start button. It’s worth using Hibernate if you habitually leave your PC on overnight and it saves the rigmarole of Windows loading after a normal shutdown. Nevertheless, you should put your PC through a normal shutdown cycle at least once a week as it gives Windows an opportunity to flush out its memory and clear out the cobwebs that build up during continuous operation.

Finally, if you are experiencing shutdown problems in Windows 9x (98/SE/ME) it’s usually due to APM conflicts, these often show up in Device Manager (System in Control Panel), look for yellow exclamation marks next to System Devices. Microsoft has put together ‘Troubleshooters’ to help you diagnose and fix APM problems, Windows 98 users should go to:

http://support.microsoft.com/default.aspx?scid=/support/

windows/tshoot/apm98/default.asp

The Windows ME troubleshooter can be found at:

http://support.microsoft.com/?kbid=273746

Next week – Windows XP Tips

JARGON FILTER

ATX

Advanced Technology Extended – set of specifications for the design of PC motherboards and power supplies

ENERGY STAR

US Government backed initiative to promote energy saving and protect the environment

TROUBLESHOOTER

Simple step-by-step procedure to help locate and fix common problems

TIP OF THE WEEK

Windows 98 has more than its fair share of power management problems, some of which were fixed in later releases but if your PC is acting up or refusing to shut down you should try the Microsoft Power Management Troubleshooting Tool. This monitors your PC when it shuts sown and generates a text file report with potential problems flagged up in red. Pmtshoot is free and can be downloaded from the Microsoft web site at:

http://support.microsoft.com/default.aspx?scid=

KB;en-us;q185949