If you already have a 3TB drive, you can check to see whether that drive is being properly recognized by booting up the system and looking in the BIOS to verify that the capacity is correctly reported. For operating systems that don't support booting from 3TB, you'll need to boot from a smaller drive and use the 3TB drive as auxiliary storage. Perform the same BIOS check, and then download and employ any required drivers and/or partitioning software the drive maker supplied. If you use third-party partitioning software, make sure to use the GPT, not MBR, partitioning scheme.

Note that NTFS is limited to 2^32 clusters, also known as groups of sectors. That means you must format the drive with at least 1024-byte clusters, or you'll fall prey to the formula I talked about earlier. The default is 4096, which allows up to 16TB; however, converting FAT partitions to NTFS often results in 512-byte clusters. If you're trying to move a FAT partition to your new drive--don't. You're better off creating a new partition, reinstalling the OS, and restoring the files you backed up (it's always wise to back up before doing any partitioning operations). This is because the FAT partition will in all likelihood be misaligned with the Advanced Format of your new drive.

Tip: With drivers or programs that don't allow a full 3TB partition, you can use Windows dynamic volumes to combine two partitions into a single drive letter.

Though not strictly a 3TB issue, all of the shipping also use Advanced Format--a low-level storage scheme employed on newer drives. AF uses larger 4KB data sectors, an approach that improves performance and diminishes the number of addresses required for any given amount of data. If you transfer legacy partitions via image backups to an AF drive, or if you format an AF drive with XP, the older 512-byte sectors might not align correctly with the new scheme.