Microsoft has confirmed the existence of a flaw in its USB 2.0 drivers for Windows XP Service Pack 2 that can cause a notebook to consume power at a faster-than-expected rate when using a peripheral device. When a peripheral device was connected to a USB (universal serial bus) 2.0 port, the notebook’s battery life plunged at a greater rate than would normally be expected from the use of a peripheral such as a mouse or storage key. At the time that details of the flaw were published, Intel denied its processors or chipsets were the responsible for the issue. And Microsoft refused to confirm until yesterday that the software company was responsible for the battery performance problem.