Although it’s more of a nuisance than a catastrophe in the making, but older computers, PDAs and DVRs may not automatically update their times when daylight-saving comes three weeks early this year — on March 11. The date change was established by the federal Energy Policy Act of 2005, which was passed to get Americans to cut energy consumption. The thinking is that less energy will be used toward the end of the day if the sun’s out later. For years, most of the nation has set clocks ahead on the first Sunday of April. Few computer experts think the new date will make a big difference. Consumers can prepare for the change by using a rule of thumb: If a computer or device is a bit older, it may not correct the time automatically. Any Microsoft operating system older than Windows XP may not recognize the new time change come March 11. For more information, customers can visit http://support.microsoft.com/gp/cp_dst. Older personal digital assistants or digital video recorders, for example, may not adjust and you might have to set those manually; you should consult the manufacturers of their devices for instructions.