"By early 2011 all hard drives will use an "advanced format" that changes how they go about saving the data people store on them.
The move to the advanced format will make it easier for hard drive makers to produce bigger drives that use less power and are more reliable.
However, it might mean problems for Windows XP users who swap an old drive for one using the changed format. In a bid to limit the misalignment, hard drive makers are producing software that ensures 512 sectors line up with 4K ones.
Those most likely to see the performance problems are those building their own computers or swapping out an old drive for one that uses the new format."