Hardware makers like Asus, Dell, or Lenovo spend a great deal of money tuning those drivers and creating an optimized profile that trades off some performance for battery life, Aul said. Microsoft itself released a firmware update last Friday for the Surface Pro 2 that significantly improves how the OS interacts with the Intel Haswell processor, improving battery life, he said. Apple's Boot Camp simply doesn't go that extra mile.
At face value, Microsoft's explanation is plausible. But could optimized drivers really wave away a two-hour difference in battery life?
Others have suggested alternative explanations. For example, Windows is chock-full of background processes, some of which are polling either the Internet, CPU, or disk for information or updates. At press time, for example, my PC is running eight applications, plus 118 background processes. Could those be adversely affecting battery life?
Aul said they could not. "We spent a great deal of time tuning" the system for I/O prioritization, he said. That means Windows spends a great deal of effort trying to avoid spinning up the disk or touching the CPU for system activities, such as indexing the disk. But if a user is calling up a photo or an application, Windows will piggyback on the request and accomplish a few key tasks. "We want to do that and get out of the way," Aul said.
Extend Windows' battery life even longer
It is possible, however, that a few poorly-tuned, third-party applications may contribute to a decline in battery life, Aul noted. "For people that used to get great battery life, that's usually the culprit," he said.
Windows also allows users to configure their power settings, either through ultiities provided by the computer manufacturer or via Windows itself. For the latter, the simplest way is to click the small battery icon on the system tray on the lower right. This will bring up a snapshot of the remaining batter charge, and the estimated time to fully exhaust the battery.
If you'd like, you can go further and create your own power plan. In general, a laptop's display and backlight suck up 20 to 25 percent of the typical power within a PC, so telling the laptop to automatically shut them down within a few minutes of inactivity can extend battery life a bit further.
Windows also offers more aggressive options, within the "Control Panel > Hardware and Sound > Power Options > Edit Plan Settings" menu. From here, select the "Change advanced power settings" at the bottom of the window." In the advanced settings, you have the option of limiting the available CPU speed and even controlling the fan.
Keep in mind that this may be overkill. "I usually don't recommend turning on the power saver unless your machine is already overpowered," Aul said. "If you're going to play some games, turning on the power saver defeats the purpose." And as for the advanced options, "I usually don't recommend people tinker with that stuff."
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