Hard disk are about to go through the biggest update in more than 30 years, and the change will take place on or near January 31, 2011. Hard disks currently use a 512 byte sectors for storing data which made sense when hard disks were small. But with drivers reaching into the 1,000 MB and larger, it is time to change to a 4 byte sector, known as advanced format.
Most of the newer operating systems can read the advanced format and they include the following:
Windows 7, Vista, OS X Tiger, Leopard, Snow Leopard and versions of the Linux kernel released after September 2009 are all 4K aware.
But it is this one statement you should be aware of:
To help Windows XP cope, advanced format drives will be able to pretend they still use sectors 512 bytes in size.
When reading data from a drive this emulation will go unnoticed. However, said Mr Burks, in some situations writing data could hit performance.
The hard disks will emulate 512 byte sectors, but I personally believe that using a hard disk that supports 512 bytes may be preferable. I would recommend buying a hard disk before the change happens just to be safe. Of course this may force some to make the switch to a newer OS.