Notebook PC users who upgrade to Microsoft's Windows Vista may have to disable some of the new operating system's flashy graphics features to avoid seeing a decrease in battery life compared to Windows XP.
The drop will come from the extra power needed to run the high-end processors, graphics cards and memory capacity required to support Vista. Microsoft has designed the new OS to deliver novel visual effects such as translucent "Aero" windows on the desktop interface and improved performance as a digital media hub. The business version of the OS was released last month with the consumer version due out next month.
PC and hardware vendors see Vista as a windfall because it requires faster, more powerful computers. But just as sport utility vehicles burn more gasoline than sedans, the extra power comes at a price.
"Vista demands more compute resources for a given application than XP does. So you need a heavier battery or you will have shorter battery life because of the greater demand for watts," chief technology officer of AMD, Phil Hester, said.
Dell also said that Vista's appetite for computing resources would increase its draw on battery power.
"If Vista is run in full Aero mode, with none of the Vista-provided power management settings turned on, it is likely to demand more power, and have an impact on battery life," Dell spokesperson, Ira Williams, said in an email. "That said, if you run Vista in battery-optimised mode (using non-3D interface), we would not expect the battery life to be significantly different from XP in that scenario."
A Microsoft spokesperson confirmed that Vista would allow users to disable or tune down graphics as part of a power management package meant to keep Vista battery life on par with Windows XP. But she said the graphics had a smaller effect on battery life than other hardware in the PC.
"Although it is true that the Windows Vista Aero theme and components can use more resources than previous versions of Windows, the relative impact to battery life is minimal," Microsoft person, Kristin Farmer, said.
"Microsoft is working with device manufacturers to ensure their device drivers are optimally tuned for performance and power savings. We recognise that battery life isn't just a Microsoft issue and involves our partner's decisions as well."
Microsoft has designed Vista to allow notebook PC users to save battery power by turning down the screen brightness, volume, wireless networking and other attributes, according to the company's website. Vista also has a power-conservation mode called sleep, similar to the standby and hibernate modes in previous versions of Windows.
A spokesperson for Gateway agreed Microsoft's power conservation steps could make a difference in compensating for the extra hardware.
"We've done extensive testing and we haven't seen [shortened battery life]," Gateway spokesperson, Kelly Odle, said. "While it is true that Vista has higher system requirements than XP, it also has more sophisticated mechanisms to allow for power savings."
Still, users who needed to preserve battery life would face a tradeoff in giving up some of the most impressive new features, an IDC analyst, Richard Shim, said.
"It's a common criticism that any new Windows OS will have a toll on battery life," Shim said. "If you look back at XP and Windows 98, it took a while for folks to learn how to optimize the hardware. And as the PC market continues to rely on notebooks to drive shipment growth, this will be a big thing."
Notebook PC users could manage power by choosing to reduce the time it takes their processors and hard drives to switch into hibernation mode, turn off their sound and Wi-Fi, avoid running 10 applications at once, and turn down the brightness of their screens -- the one component that consumed more battery power than any other computer part, Shim said.
Some hardware makers were also helping out, as they were striving to squeeze an extra 2 per cent to 5 per cent efficiency out of the chipset, graphics component and BIOS, Shim said. However, they faced a limited power budget, since battery technology had not improved significantly in recent years, and PC vendors were unlikely to specify a larger cell, since that would add to the PC's size, weight and cost.
"That can add up to savings, but it's not enough to overcome the fact that Vista is not battery-friendly," Shim said.