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ntfs max disc size
- Thread starter mattg
- Start date
This all depends...<br>
<br>
Pre Service Pack 4 Atapi can only handle a maximum of 8GB per partition, but not on the active boot partition which is limited to 7.8GB. But thats still post installation since the boot partition is limited to a created size of 4GB because of a FAT limitation under Windows NT, since the drive must be converted to NTFS after the first boot.<br>
<br>
NTFS is not really limited in size since the actually size limit is 2^64 bytes (16 exabytes or 18,446,744,073,709,551,616 bytes). I assume they would just upgrade the limit if anyone actually came up with a drive with that much space. But there is also a 2 terabyte limitation with any file system due to hardware limit in the partition table.<br>
<br>
Alternatively you could easily extend the size of any other partition, besides the boot partition, after Windows NT is installed.<br>
<br>
Hopes this helps. <p>John D. Saucier<br><a href=mailto:jsauce@net1plus.com>jsauce@net1plus.com</a><br><a href= Backup</a><br>
<br>
Pre Service Pack 4 Atapi can only handle a maximum of 8GB per partition, but not on the active boot partition which is limited to 7.8GB. But thats still post installation since the boot partition is limited to a created size of 4GB because of a FAT limitation under Windows NT, since the drive must be converted to NTFS after the first boot.<br>
<br>
NTFS is not really limited in size since the actually size limit is 2^64 bytes (16 exabytes or 18,446,744,073,709,551,616 bytes). I assume they would just upgrade the limit if anyone actually came up with a drive with that much space. But there is also a 2 terabyte limitation with any file system due to hardware limit in the partition table.<br>
<br>
Alternatively you could easily extend the size of any other partition, besides the boot partition, after Windows NT is installed.<br>
<br>
Hopes this helps. <p>John D. Saucier<br><a href=mailto:jsauce@net1plus.com>jsauce@net1plus.com</a><br><a href= Backup</a><br>
Here is anarticle for some consideration also as there is a hidden portion of the install that has dos limits when you install you are limited to a 4gb system partition. you can then feel free to use something like partition magic to resize the partition.<br>
<br>
<br>
Although Windows NT 4.0 can in theory support partitions of up to 16 exabytes in<br>
size using the NTFS file system, the maximum size of the system partition is<br>
limited to 7.8 gigabytes (GB).<br>
<br>
MORE INFORMATION<br>
================<br>
<br>
The system partition is defined as the partition containing the files needed for<br>
the initial system startup. For Windows NT, the files are NTDetect.com, NTLDR,<br>
Boot.ini, and sometimes Ntbootdd.sys.<br>
<br>
A boot partition is defined as the partition containing the system files. For<br>
Windows NT, this is the partition containing the %SystemRoot%\System32 folder.<br>
<br>
The system partition and boot partition can be on the same partition or on<br>
different partitions. Because there can be multiple operating systems installed<br>
on a single computer, a computer can have multiple boot partitions, but a<br>
computer has only a single system partition.<br>
<br>
When an Intel-based computer first boots, a number of things occur that result in<br>
the operating system being loaded and started. This process, known as the<br>
bootstrap process, has inherent hardware and software limitations beyond which<br>
Windows NT cannot operate. It is these limitations that prevent Windows NT 4.0<br>
from using a partition larger than 7.8 GB as a system partition.<br>
<br>
During the bootstrap process, the only mechanism available to Windows NT (or any<br>
other operating system) to access the drive is a set of functions in the BIOS<br>
known as Interrupt 13 (INT13). The INT13 functions allow low-level code to read<br>
from and write to the drive by addressing a specific sector on the drive. When<br>
the INT13 architecture was developed back in the early 1980s, the possibility of<br>
multi-gigabyte hard disks was not taken into consideration. The INT13 functions<br>
define 24 bits to describe a sector on the hard disk. This breaks down to a<br>
maximum of 256 heads (or sides), 1024 cylinders, and 63 sectors. With these<br>
numbers, only 256*1024*63 (or 16,515,072) sectors can be used with INT13<br>
functions. At a standard 512 bytes per sector, this is 8,455,716,864 bytes, or<br>
approximately 7.8 GB. Note that for most modern drives, the computer's BIOS must<br>
support some form of sector translation for the BIOS functions to address the<br>
first 7.8 GB of disk space. The BIOS in virtually all modern computers supports<br>
"Logical Block Addressing," which allows INT13 functions to address the first<br>
7.8 GB of drive space independent of the drive's physical geometry.<br>
<br>
The INT13 functions are the only means available to the operating system to gain<br>
access to the drive and system partition until the operating system loads<br>
additional drivers that allow it to gain access to the drive without going<br>
through INT13. Therefore, Windows NT 4.0 cannot use a system partition larger<br>
than 7.8 GB. In fact, the entire system partition must be entirely within the<br>
first 7.8 GB of the physical disk. Windows NT can use a 7.8-GB system partition<br>
only if the partition begins at the start of the physical drive.<br>
<br>
NOTE: Partitions other than the system partition are not affected by the these<br>
limitations.<br>
<br>
Other operating systems, such as Microsoft Windows 95 OEM Service Release 2,<br>
Microsoft Windows 98, and Microsoft Windows 2000, can boot from larger<br>
partitions because these operating systems were written after the computer<br>
industry defined a new standard for BIOS INT13 functions (the "INT13<br>
extensions"
and implemented this new functionality on manufactured<br>
motherboards. Because Windows NT 4.0 was written before this new standard was<br>
invented, Windows NT 4.0 is unaware of this new technology and is unable to use<br>
its features.<br>
<br>
When you are installing Windows NT 4.0, you can create a system partition with a<br>
maximum size of 4 GB. This occurs because Setup first formats the partition<br>
using the FAT file system. If you want to use an NTFS partition, the partition<br>
is converted to NTFS after the first reboot. The FAT file system has a file<br>
system limitation (unrelated to any BIOS limitations) of 4 GB. When you perform<br>
an unattended installation, use of the ExtendOEMPartition directive in an<br>
Unattend.txt file can expand the system partition to a maximum of 7.8 GB.<br>
<br>
In the future, additional limitations may come into play as well. Although the<br>
NTFS file system can address 16 exabytes of disk space in a single partition,<br>
current disk-partitioning schemes store partition information in structures that<br>
limit partitions to 2^32 sectors, or 2 terabytes, in size. The ATA hardware<br>
interface uses 28-bit addressing, which supports drives that are 2^24 sectors,<br>
or 137 GB, in size. These limitations may apply to partitions other than the<br>
system partition as well.<br>
<br>
Note that file system limitations and hardware limitations exist independently of<br>
each other, and the most restrictive of the two is the determining factor in the<br>
maximum partition size. Another factor to consider when you are troubleshooting<br>
partitioning problems is that hard disk manufacturers often use "decimal<br>
megabytes" (1 megabyte = 1,000,000 bytes), whereas Windows NT uses "binary<br>
megabytes" (1 megabytes = 1,048,576 bytes). Using both definitions of a megabyte<br>
in calculations can often account for "lost" disk space. Also, this article<br>
assumes a sector size of 512 bytes in all calculations. Although a 512-byte<br>
sector has become a de facto industry standard, it is possible that disk<br>
manufacturers could produce drives with a different sector size. This would<br>
result in a corresponding change in partition limits. Partitions are based on<br>
cylinder, head, and sector calculations, not on byte calculations. Therefore, a<br>
change in bytes per sector causes a change in bytes per partition.<br>
<br>
<br>
Although Windows NT 4.0 can in theory support partitions of up to 16 exabytes in<br>
size using the NTFS file system, the maximum size of the system partition is<br>
limited to 7.8 gigabytes (GB).<br>
<br>
MORE INFORMATION<br>
================<br>
<br>
The system partition is defined as the partition containing the files needed for<br>
the initial system startup. For Windows NT, the files are NTDetect.com, NTLDR,<br>
Boot.ini, and sometimes Ntbootdd.sys.<br>
<br>
A boot partition is defined as the partition containing the system files. For<br>
Windows NT, this is the partition containing the %SystemRoot%\System32 folder.<br>
<br>
The system partition and boot partition can be on the same partition or on<br>
different partitions. Because there can be multiple operating systems installed<br>
on a single computer, a computer can have multiple boot partitions, but a<br>
computer has only a single system partition.<br>
<br>
When an Intel-based computer first boots, a number of things occur that result in<br>
the operating system being loaded and started. This process, known as the<br>
bootstrap process, has inherent hardware and software limitations beyond which<br>
Windows NT cannot operate. It is these limitations that prevent Windows NT 4.0<br>
from using a partition larger than 7.8 GB as a system partition.<br>
<br>
During the bootstrap process, the only mechanism available to Windows NT (or any<br>
other operating system) to access the drive is a set of functions in the BIOS<br>
known as Interrupt 13 (INT13). The INT13 functions allow low-level code to read<br>
from and write to the drive by addressing a specific sector on the drive. When<br>
the INT13 architecture was developed back in the early 1980s, the possibility of<br>
multi-gigabyte hard disks was not taken into consideration. The INT13 functions<br>
define 24 bits to describe a sector on the hard disk. This breaks down to a<br>
maximum of 256 heads (or sides), 1024 cylinders, and 63 sectors. With these<br>
numbers, only 256*1024*63 (or 16,515,072) sectors can be used with INT13<br>
functions. At a standard 512 bytes per sector, this is 8,455,716,864 bytes, or<br>
approximately 7.8 GB. Note that for most modern drives, the computer's BIOS must<br>
support some form of sector translation for the BIOS functions to address the<br>
first 7.8 GB of disk space. The BIOS in virtually all modern computers supports<br>
"Logical Block Addressing," which allows INT13 functions to address the first<br>
7.8 GB of drive space independent of the drive's physical geometry.<br>
<br>
The INT13 functions are the only means available to the operating system to gain<br>
access to the drive and system partition until the operating system loads<br>
additional drivers that allow it to gain access to the drive without going<br>
through INT13. Therefore, Windows NT 4.0 cannot use a system partition larger<br>
than 7.8 GB. In fact, the entire system partition must be entirely within the<br>
first 7.8 GB of the physical disk. Windows NT can use a 7.8-GB system partition<br>
only if the partition begins at the start of the physical drive.<br>
<br>
NOTE: Partitions other than the system partition are not affected by the these<br>
limitations.<br>
<br>
Other operating systems, such as Microsoft Windows 95 OEM Service Release 2,<br>
Microsoft Windows 98, and Microsoft Windows 2000, can boot from larger<br>
partitions because these operating systems were written after the computer<br>
industry defined a new standard for BIOS INT13 functions (the "INT13<br>
extensions"
and implemented this new functionality on manufactured<br>motherboards. Because Windows NT 4.0 was written before this new standard was<br>
invented, Windows NT 4.0 is unaware of this new technology and is unable to use<br>
its features.<br>
<br>
When you are installing Windows NT 4.0, you can create a system partition with a<br>
maximum size of 4 GB. This occurs because Setup first formats the partition<br>
using the FAT file system. If you want to use an NTFS partition, the partition<br>
is converted to NTFS after the first reboot. The FAT file system has a file<br>
system limitation (unrelated to any BIOS limitations) of 4 GB. When you perform<br>
an unattended installation, use of the ExtendOEMPartition directive in an<br>
Unattend.txt file can expand the system partition to a maximum of 7.8 GB.<br>
<br>
In the future, additional limitations may come into play as well. Although the<br>
NTFS file system can address 16 exabytes of disk space in a single partition,<br>
current disk-partitioning schemes store partition information in structures that<br>
limit partitions to 2^32 sectors, or 2 terabytes, in size. The ATA hardware<br>
interface uses 28-bit addressing, which supports drives that are 2^24 sectors,<br>
or 137 GB, in size. These limitations may apply to partitions other than the<br>
system partition as well.<br>
<br>
Note that file system limitations and hardware limitations exist independently of<br>
each other, and the most restrictive of the two is the determining factor in the<br>
maximum partition size. Another factor to consider when you are troubleshooting<br>
partitioning problems is that hard disk manufacturers often use "decimal<br>
megabytes" (1 megabyte = 1,000,000 bytes), whereas Windows NT uses "binary<br>
megabytes" (1 megabytes = 1,048,576 bytes). Using both definitions of a megabyte<br>
in calculations can often account for "lost" disk space. Also, this article<br>
assumes a sector size of 512 bytes in all calculations. Although a 512-byte<br>
sector has become a de facto industry standard, it is possible that disk<br>
manufacturers could produce drives with a different sector size. This would<br>
result in a corresponding change in partition limits. Partitions are based on<br>
cylinder, head, and sector calculations, not on byte calculations. Therefore, a<br>
change in bytes per sector causes a change in bytes per partition.<br>
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