OSDIIDED - OS/2 WARP AND ENHANCED IDE DRIVES GREATER THAN 528 MB 02/09/96 ======================================================================= OS/2 Warp (All Versions) and Enhanced IDE Drives Greater Than 528 MB ======================================================================= Please Read Entire Document for Full Explanation of Procedures -------------------------------------------------------------- DESCRIPTION If you have an Enhanced IDE hard disk with a capacity greater than 528 MB (more than 1024 cylinders), be aware of the following restrictions: * The file allocation table (FAT) file system is limited to partition sizes of less than 1024 cylinders. * The high performance file system (HPFS) can support data partitions greater than 1024 cylinders; however, the partition where OS/2 is started from cannot be more than 1024 cylinders. The HPFS can support drives of up to 2 GB. RESOLUTION If your BIOS allows you to define a large drive, you should be able to format the area above the 1024 cylinder range as an HPFS. The only restrictions are that Boot Manager, FAT partitions, and startable partitions cannot cross the 1024 cylinder address. There is no problem with HPFS data partitions. OS/2 does not use the system BIOS, but it is still in use while starting; thus, the limitation. IDE Drives Greater Than 528 MB ------------------------------ No Translating BIOS or Utilities -------------------------------- These restrictions apply: * The BIOS, DOS, and FAT limitation is that the startup (boot) partition and FAT partition must be contained in the first physical 528 MB partition. * An HPFS data (non-startup) partition does not have this restriction and can be greater than 528 MB, if it is not the startup (boot) partition Translating System BIOS ----------------------- Translating System BIOS has none of the above restrictions. All IBM systems that come with hard disks greater than 528 MB hard disks have translating BIOS. This includes desktop, Aptiva and mobile systems. Most Tier 1 PCM systems also come with translating BIOS. A notable exception is Dell. With translating BIOS you can have a single partition the size of the drive, 528 MB, 720 MB, or 1 GB. Without translating BIOS, you cannot access anything above 528 MB as a single drive letter. Translating BIOS Utilities -------------------------- * ONTRACK 6.03 is the most popular translating BIOS utility program that is shipped with PC Company and Western Digital optional hard disks greater than 528 MB. You must first install ONTRACK 6.03 under DOS to have the drive translated before starting OS/2 Warp. You need the latest IBM1S506.ADD driver (OS/2 Warp Fullpack version) and the latest FDISK. You can remove ONTRACK 6.03 by installing Version 7.0 over it and then removing 7.0. ONTRACK 7.0 does not require IBM1S506.ADD, but it does require the latest FDISK. FDISK preserves the previous contents of the Master Boot Record. * Micro House EZ-Drive 4.02 also works. You again need the new FDISK with this as well. EZ-Drive 2.03 is the version supplied to Seagate. For OS/2 Warp, there is the restriction that Boot Manager cannot coexist with EZ-Drive. Contact the vendor for details. Other Related Defects --------------------- Easy Installation defaulted to a partition size equal to the size of the drive. On an IDE hard disk greater than 528 MB, this causes FDISK and the installation to fail. In OS/2 Warp Fullpack, FDISK allows only a partition size that is startable. The startable size depends on whether or not there is translation. A query to FDISK now shows the translation of 1024 cylinders to MB, so you know what the largest startable partition size is if the drive is not translated. A size of 1024 cylinders does not always map to 528 MB. None of this applies to SCSI drives, which have translated BIOS and support sizes greater than 528 MB. ______________________________________________________________________ IBM disclaims all warranties, whether express or implied, including without limitation, warranties of fitness and merchantability with respect to the information in this document. By furnishing this document, IBM grants no licenses to any related patents or copyrights. Copyright (c) 1994, 1996 IBM Corporation. Any trademarks and product or brand names referenced in this document are the property of their respective owners. Consult your product manuals for complete trademark information.