Windows 7 Mobility Features : Power Management (part 2) - Power Options Control Panel

3. Power Options Control Panel

Windows 7's power options are, go figure, configured via the Power Options control panel, which is available in Control Panel => Hardware and Sound => Power Options on any kind of PC. (For some reason, there were different ways to access this control panel in Windows Vista, depending on whether you were using a portable PC or a desktop PC.) As always, Start Menu Search is your friend: just type power options into Start Menu Search to get there quickly, regardless of what kind of PC you have.) Shown in Figure 4, this control panel initially presents a selection of two of the three power plans mentioned previously. (Again, you may see different options if your PC maker decided to configure its own custom plan.)

Figure 4. Power Options is your central management console for the Windows 7 power management features.

There's a lot more going on here, however, and some things have changed since Windows Vista. On the left side of the window are a number of power management–related tasks. If you're using a mobile computer of any kind, navigate through each of these options to ensure that your system is configured exactly the way you want it. These options are interesting to desktop PC users as well. You can also quickly access the screen brightness settings directly from this window, a new addition in Windows 7.

3.1. Requiring a Password on Wakeup

The first option, "Require a password on wakeup," varies a bit according to your system's capabilities and there's a lot more going on here beyond the password option hinted at in the link. On a typical desktop PC, this power plan settings page resembles what is shown in Figure 5.

Figure 5. Desktop PCs don't have many power management options related to hardware features.

But when you view this page on a typical notebook computer, you'll see the options shown in Figure 6. These options are directly related to the additional hardware buttons and features included with mobile computers.

Figure 6. Notebook computers and other mobile PCs offer power management options related to the lid and other hardware features.

Here, you can modify how Windows 7 reacts when you press the PC's power button; press the sleep button; or, on portable computers configured with a lid-based display, when you close the lid. Each of these options has different settings for when the system is operating on battery power versus plugged in.

Complementing the "Require a password on wakeup" option described previously, this dialog also includes a single wakeup-related option that determines whether you need to log on again each time the system wakes up after being in the sleep state. By default, Windows 7 does require you to log on again to unlock the computer as a security measure. We strongly advise leaving this feature enabled, especially if you're a mobile computer user who often accesses the PC on the road.

Returning to the Power Options display, the following additional options are available on the left side of the window.

3.2. Choose What the Power Buttons Do

Humorously, this option triggers the same display described previously. The top half of the dialog relates to this option.

3.3. Choose What Closing the Lid Does

This option, which is available only on portable computers with a lid, also brings you to the same dialog described previously. Why three different options all land on the same display is a question best saved for the UI wizards at Microsoft. (And, on a related note, how was this silliness carried over from Windows Vista to Windows 7 with nary a change?)

3.4. Create a Power Plan

When you click this option, you're brought to the Create a Power Plan page, a short wizard you can use to create your own power plan:

This is all well and good, but the short wizard you just used doesn't really provide access to all of the power management options you can configure; and isn't that the point of this exercise—to create a custom power plan that exactly matches your needs and desires?

To modify your custom plan (or an existing preset plan for that matter), click the Change plan settings link next to the plan name in question. This brings you to a dialog that resembles the second phase of the wizard just described, but with one difference: there's now a Change advanced power settings link. Click that link to modify other settings. Doing so opens the Power Options Advanced settings dialog, shown in Figure 10.

The Power Options Advanced settings window is, by nature, confusing. The window itself is not resizable, so it provides only a postage-stamp-size view of the many power management features you can customize. More problematic, you have to expand nodes in a tree control—arguably the worst PC user interface element of all time—to find all the options. Nonetheless, it's worth the trouble if you're serious about modifying a power plan.

Figure 10. Use this rather complicated dialog to handcraft your power plan using every single power management option available to Windows 7.

Here are the power management options available via this dialog:

• Balanced/Power saver/High performance: This setting, which is named after the power plan you're changing, lets you configure whether the system requires a password when it wakes from sleep. (Portable PCs divide this option into two sub-options: one for when the system is plugged in and one for when it's attached to a power source.) The default option is Yes for both, and you should leave them alone unless you're interested in playing Russian Roulette with private data stored on your PC.

• Hard disk: Use this option to configure the hard disk to wind down after a period of time to preserve power. (As with many settings, portable PCs have separate options for battery and plugged in.) On battery, you want this time to be reasonably low, maybe five minutes, but you should also configure a desktop PC or power-attached portable PC to wind down the hard drive after a short period as well, if only to conserve power consumption.

• Desktop background settings: This setting determines what should happen when you're using a desktop theme with multiple images (in a slide show). There are two settings, one for battery power, and one for plugged in, and two possibilities for both: Available, which leaves background image changing on, and Paused, which prevents the background from changing to save battery power.

• Wireless Adapter Settings: This option may seem fairly esoteric, but it can affect the performance of your wireless card (a common feature in portable PCs) and the PC. This feature is of interest only to portable PC users. By default, under most power management plans, the wireless adapter is set to run with maximum performance. The only exception is the Power Saver plan, on battery power: in this mode, the wireless adapter is configured to run under maximum power-saving mode, which conserves power by lowering the effectiveness of the wireless radio. You can configure this option as follows: Maximum Performance, Low Power Saving, Medium Power Saving, and Maximum Power Saving. Frankly, this might be too fine-grained for most people, and we've had little success determining what effects each state really has on power management and performance overall. Given this, our recommendation is to leave this setting at its default, based on which power plan you based your own plan on.

• Sleep: This section supports four options: Sleep after, Allow hybrid sleep, Hibernate after, and, new to Windows 7, Allow wake timers. The first and third are straight-forward, but the second and fourth options might be confusing.

  Newer PCs support a new type of Sleep mode called Hybrid Sleep, which enables the machine to appear to turn off and on almost immediately, like a consumer electronics device. If you have a PC manufactured after mid-2006, it might support this feature, so experiment with enabling Hybrid Sleep, especially since it likely won't be enabled by default. If it works well, use this instead of Hibernation, as Hybrid Sleep is essentially a replacement for that older form of power management. Otherwise, you might want to enable Hibernation, which was a major power management feature in Windows XP. Hibernation is faster than turning on and off the PC, but much slower than Sleep or Hybrid Sleep. Although the PC is turned off, it preserves the state of the system so you can get up and running with your applications more quickly.

  Allowing the user to configure wake timers is new to Windows 7. Wake timers are used by applications and the OS to wake an idle PC to perform certain tasks that would be impossible if the system were in Sleep mode. By default, wake timers are disabled.

• USB settings: Your PC can optionally turn off selected USB devices when it enters certain power management states. This can improve battery life, as USB devices, like mice, storage devices, cameras, and other devices, draw power from the PC. However, it also prevents you from using these attached devices. Suspended USB devices will wake up again once the system is plugged in to a power source. Power buttons and lid: What you see here varies according to the hardware capabilities of your PC, but you can usually draw the distinction neatly between desktop PCs and portable PCs. Desktop PCs typically see two options: Power button action and Sleep button action, whereas portable PCs have an additional option: Lid close action. Power button action determines what happens when you press the hardware On/Off switch on the PC (this can be configured separately for battery power and plugged in). Options include Do nothing, Sleep, Hibernate, and Shut Down. Lid close action behaves similarly, but refers to what happens when the lid of a portable computer is shut: you can choose between the same four options. If your PC has a dedicated Sleep button (as do many portable machines), the Sleep button action provides the same configurability, but for that particular button.

• PCI Express: This option should typically not be changed. On a desktop PC, it should be set to Off so that hardware expansion cards attached via the PCI Express bus are always available. On portable PCs, it is set to Maximum Power Savings or Moderate Power Savings, depending on the power plan and whether the system is running on battery power.

  NOTE

  Windows Vista supported a fourth option here, called Start menu power button. In Windows 7, this option is not related to power management—which makes sense—and is instead available from the Start menu tab of the Taskbar and Start Menu Properties window, shown in Figure 11. (You can access this UI by right-clicking the Start button and choosing Properties.)

  Figure 11. The Start menu power button is fully configurable; you just need to know where to look.

  

• Processor power management: This setting has some of the biggest impact on performance and battery life and should be carefully chosen. Here, you can fine-tune how much processor power is used under certain states. We described how the default power plans affect processor performance, and you should use that as a guideline. Note, however, that you will likely be disappointed with the system's performance while doing multimedia tasks if 100 percent of the processor's performance isn't available. Note that whereas Windows Vista supported the Minimum processor state and Maximum processor state options, Windows 7 adds a third, new option: System cooling policy. This option is designed for PCs with active cooling systems only and should not be modified unless you know what you're doing.

• Display: Here, you can specify how quickly Windows 7 dims and turns off the display, which is pretty straightforward, and configure the display brightness in both normal and dimmed modes.

• Multimedia settings: One of the nicest features of Windows 7 is that it makes it very easy to share media such as music, videos, and photos from PC to PC and even across the Internet. However, when you're running on battery power, media sharing can be overly resource intensive and thus exacerbate energy consumption, so you may want to curtail media sharing on battery power. Available options include Allow the computer to sleep, Prevent idling to sleep, and Allow the computer to enter Away mode. The first two are self-explanatory, and portable computers should always be allowed to enter Sleep mode while on battery power. The final option, however, might be confusing. Away mode is a modern power management option (related to media sharing and the Windows Media Center feature) that enables background media tasks, such as Media Center recording of TV shows and media sharing, to occur in the background even while the system otherwise appears to be asleep. This mode thus provides most of the power management benefits of Sleep while still allowing media sharing to occur.

• Battery: This option, available only on portable PCs, determines how the system battery is configured to warn you or perform certain actions at specific times, such as when the battery is low or critically low. Options include Critical battery action (what happens when the battery life falls to a "critical" level), Low battery level (at what percentage of full the battery is considered "low"), Critical battery level (at what percentage of full the battery is considered "critical"), Low battery notification (whether the system informs you of the transition into this state), Low battery action (what happens when the battery life falls to a "low" level), and, new to Windows 7, Reserve battery level (an additional warning level between "low" and "critical," kind of like the red area on your car's gas gauge right before true Empty).

• Third-party power management settings: Many hardware makers have created their own advanced power management settings, which can be exposed to the user via this control panel and configured accordingly. For example, display card maker ATI has an ATI Graphics Power Settings option that helps you configure how ATI Mobility Radeon graphics products impact overall power consumption.

3.5. Choose When to Turn Off the Display

This option triggers the same dialog previously described (Edit Plan Settings).

3.6. Change When the Computer Sleeps

This option also triggers the same dialog described previously in the "Requiring a Password on Wakeup" section.

NOTE

In Windows Vista, you could delete custom power plans in a straightforward manner. Oddly, this capability was removed from the Power Options control panel UI in Windows 7.