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High-capacity HDD is not recognized (>128 GB)

It become more and more familiar that hard drives get capacity exceeding 128 GB and when installed on some machines, the system shows only 128 gigabytes.

Causes of problem

This problem may be due to two separate causes:
1 Physical Cause: The motherboard cannot managing more than 128 GB
2 Software Cause: The operating system (Windows, Linux, MacOS, etc..) does not have the capacity of managing large disk.

Scientific explanation

The 128 GB limit comes from addressing mode disk drive (LBA - Logical Block Addressing), limited to 28 bits. Indeed, with 28 bits, it is possible to send 2 for 28 sectors of 512 bytes, totaling 137438953472 Bytes, corresponding to 128 GB (actually 137 GB if it is considered that a gigabyte is 1 billion bytes and not 1000 ^ 2 bytes).

Up to 2002, the standard ATA-6 allows you to address the areas of disk 48-bit (LBA48), or for sectors of 512 bytes 2 ^ 48 = 144115188075855872 * 512 bytes, ie 256 Petabytes !


Enable support at the operating system

To enable the computer to recognize this capacity,you should ensure that the operating system supports LBA48. For Windows systems, it is from Windows 2000 Service Pack 3 and Windows XP Service Pack 1.

However, under Windows 2000 it is necessary to enable support by making a change in the registry:
Click on Start / Run and type regedit.
Scroll to: HKEY_LOCAL_MACHINE / System / CurrentControlSet / Services / Atapi / Parameters / Create a new DWORD value named EnableBigLba and set its value to 1

For systems running Windows 98, Windows 98 SE and Windows Me, an individual (Rudolph R. Loew) has developed a patch to provide support for hard disks, high-capacity:
members.aol.com/rloew1/Programs/Patch137.htm HIGH CAPACITY DISK PATCH Version 4.5 (DEMO)

Enable support at the motherboard

Then it may be necessary to enable LBA48 support at the motherboard. To do this, it may be flashing the BIOS of the motherboard: Flashing the BIOS

You should also download the latest drivers for your motherboard.

Motherboard based on Intel chipset:
Motherboard based on Via chipset:

Partitioning the disk

Finally, once the total capacity of the disk recognized, you will have to create partitions or resize existing partitions. To partition the hard disk, follow the guide:
Partitioning a hard disk

A few words of thanks would be greatly appreciated.

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