The Easy Way to Set Up a New Dual-Boot System

When you're building a new dual-boot computer, you don't have to worry about re-sizing partitions.

The Windows installer also contains a utility to create partitions. Unlike Linux installers, however, the Windows installer can't create non-Windows partitions. But that's no big deal. You just run the Windows installer first and let it create the Windows partition(s) you need, but leave the rest of the hard drive "raw" or unused to leave space for your later Linux installation.

By default, the Windows partitioner will want to create one huge partition that takes up the entire hard drive. But you can override this selection. When you get to that point (it happens very early on in the installation), simply reduce the size of the partition to whatever size you want the Windows partition to be. Exactly how big that partition should be depends on a lot of factors, but basically, you want both the Windows and Linux sides to be big enough that you won't run out of space some time in the future.

I recommend creating three "sections" on the hard drive: One for Windows, one for Linux (that actually will contain at least two partitions, because Linux needs a swap partition), and one shared partition for data that's going to be available to both systems. In past versions of this page, I recommended that the shared partition be formatted as a FAT32 partition, but I'm convinced that the Linux NTFS driver, NTFS-3G, is now up to the task of playing on NTFS playgrounds. (Most Linux distributions now install NTFS-3G by default.)

You don't have to create a shared data partition, by the way (although I recommend that you do). Linux will still be able to access the data in your Windows document folder (unless you protect or encrypt it in Windows). But creating a shared partition for documents makes things a lot simpler and cleaner. It also makes backup easier, it helps keep your documents safe if one or the other operating system crashes, and it simplifies the process of updating or upgrading the operating systems.

If you decide to create a shared data partition, you will have to re-map the Documents and Libraries shortcuts in Windows to point to the shared partition, and (possibly) create symlinks to the partition from your Linux system (the installer may do this automatically, depending on the distribution). This is an easy thing to do once the systems are installed.

Using Multiple Hard Drives

Another option you may choose for your dual-boot computer is to use multiple hard drives. There are several possible configuration options.

You could, for example, use two hard drives, and install Windows on one and Linux on the other. If you want to create a shared data partition, decide which drive it's going to live on. (If one drive is bigger than the other, you may want to partition that drive into two sections: one for the OS it's hosting, and the other for the data partition.)

Another possibility using two drives would be to partition one drive into two partitions to host both operating systems, and partition the other drive into one big partition to store the data, which would be shared by both operating systems.

If you decide to use multiple drives, it's important to make sure that Windows is installed on the first partition of the primary drive (or the primary master, if you're using PATA drives). Why? Because that's where Windows will expect to be installed, and it just makes life easier to do it that way.