- 1). Plan your hard-drive partitions. Each operating system has different requirements and must be installed on a separate volume. If your computer only has one volume, it must be repartitioned to two volumes. Due to the large disk capacity of newer hard drives, it is important to remember that Windows 98 does not recognize partitions greater than 127 GB. It is also important how these partitions are formatted. Windows XP has many performance and file security features used in the NTFS file system, but Windows 98 cannot read NTFS formatted volumes. Both operating systems support the FAT and FAT32 file systems, so any volumes both operating systems need to access be formatted with one of these two file systems. It is recommended that Windows 98 be on a FAT32 partition and Windows XP installed into a NTFS partition.
- 2). Install Windows 98 into one of the FAT32 partitions, following the on-screen instructions. It is important to install the older operating system first to prevent the operating system from overwriting XP's boot sector and start-up files.
- 3). Install Windows XP into the second partition. It is important to select New Installation (Advanced) over the Upgrade (Recommended) in the Windows Setup dialog during the installation. Upgrade will upgrade the Windows 98 partition and defeat the purpose of dual booting to both operating systems. Finish the installation according to the on-screen instructions.
- 4). Configure your dual-boot system. While your computer boots, you will now be offered a choice between Windows 98 and Windows XP operating systems. Select the operating system you wish to run or wait 30 seconds and the default choice will be made. The default operating system can be changed if needed. To change the default operating system: Boot to the Windows XP system. Open the Control Panel and double click "System." Select the "Advanced" tab. In the Startup and Recovery section, click "Settings." Under "System Startup," click the operating system you want to be the default. The amount of time the operating system choice is offered before the default is booted can also be changed in this section.
- 5). Install any hardware and software. Each operating system should be treated as a separate entity. Programs needed in both operating systems must be installed in each environment. Hardware will have to be configured for both systems separately.
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