XP SP2 & 48 bit LBA

"Tom" wrote:

"Timothy Daniels" wrote:
"Andy" wrote:
"Timothy Daniels" wrote:

"Andy" wrote
;
Contrary to popular belief the BIOS is not critical, unless during the
boot process the disk has to be accessed past the 137GB boundary
(basically applies to primary partitions larger than 250GB).


Can you think of such a scenario? The MBR is usually right at the
start of the disk, and its boot code is loaded into memory for execution,
and similarly for the boot sector of the partition containing the OS.
If the boot sector and the OS are in a partition way up high on the disk,
the code loaded into memory would be accessing it, so it would seem
that a limitation in the boot sector code or the MBR code would be the
cause, not the BIOS. Yet the Dell Common Knowledge is that the BIOS
for my circa 1999 desktop has to be updated before it can do the 137GB
cha cha.


Any code that is executed during the boot process does not directly
access the disk. Rather it uses BIOS interrupts to access the disk.
The MFT is placed in the middle of the NTFS formatted partition. The
file system of any partition whose MFT lies past the 137GB boundary
cannot be read during the boot process if the BIOS does not support
48-bit LBA. For a single primary partition, the size of that partition
is about 137GB x 2.
The setup program of Windows XP incorporating SP1 or 2 does not use
the BIOS to partition and format the disk, so it is able to partition
and format a 300GB disk as a single primary partition. However, once
it has copied the preliminary files to the disk and reboots, the
Windows XP installation will not boot up if the BIOS does not support
48-bit LBA.


Are you sure that the MFT is placed in the physical middle of the
partition and not the LOGICAL middle? In a binary tree structure,
the root could very well be at the physical start of the medium's
address space. I searched through the on-line Microsoft knowledge
base, and I couldn't find any reference to the physical middle or
address space middle of the NTFS-formatted partition as being
the location of the MFT. There *were* one or two refs to the
*logical* middle, though.



You have it correct partially as far a "logical center" but it resides in
the boot sector also, read he
http://www.ntfs.com/ntfs-mft.htm


OK. Now back to the original statement about the location of the
Master File Table. Does any part of it reside physically at the center
of the partition, or does it reside totally in the boot sector?

*TimDaniels*

"Timothy Daniels" wrote in message
...
"Tom" wrote:

"Timothy Daniels" wrote:
"Andy" wrote:
"Timothy Daniels" wrote:

"Andy" wrote
;
Contrary to popular belief the BIOS is not critical, unless during
the
boot process the disk has to be accessed past the 137GB boundary
(basically applies to primary partitions larger than 250GB).


Can you think of such a scenario? The MBR is usually right at the
start of the disk, and its boot code is loaded into memory for
execution,
and similarly for the boot sector of the partition containing the OS.
If the boot sector and the OS are in a partition way up high on the
disk,
the code loaded into memory would be accessing it, so it would seem
that a limitation in the boot sector code or the MBR code would be the
cause, not the BIOS. Yet the Dell Common Knowledge is that the BIOS
for my circa 1999 desktop has to be updated before it can do the 137GB
cha cha.


Any code that is executed during the boot process does not directly
access the disk. Rather it uses BIOS interrupts to access the disk.
The MFT is placed in the middle of the NTFS formatted partition. The
file system of any partition whose MFT lies past the 137GB boundary
cannot be read during the boot process if the BIOS does not support
48-bit LBA. For a single primary partition, the size of that partition
is about 137GB x 2.
The setup program of Windows XP incorporating SP1 or 2 does not use
the BIOS to partition and format the disk, so it is able to partition
and format a 300GB disk as a single primary partition. However, once
it has copied the preliminary files to the disk and reboots, the
Windows XP installation will not boot up if the BIOS does not support
48-bit LBA.


Are you sure that the MFT is placed in the physical middle of the
partition and not the LOGICAL middle? In a binary tree structure,
the root could very well be at the physical start of the medium's
address space. I searched through the on-line Microsoft knowledge
base, and I couldn't find any reference to the physical middle or
address space middle of the NTFS-formatted partition as being
the location of the MFT. There *were* one or two refs to the
*logical* middle, though.



You have it correct partially as far a "logical center" but it resides in
the boot sector also, read he
http://www.ntfs.com/ntfs-mft.htm


OK. Now back to the original statement about the location of the
Master File Table. Does any part of it reside physically at the center
of the partition, or does it reside totally in the boot sector?

*TimDaniels*

Yes, it resides in the center, you can note this during a defrag (especially
good defragging programs). The link I gave you said specifically that it
resides there. "A duplicate of the boot sector is located at the logical
center of the disk."

Here is an example snapshot of a defrag analysis (hope you have high speed
internet), and note the color legend regarding the MFTs to the color scheme
in the main window.

http://home.insightbb.com/~guesswho192/MFT_example.JPG

"Tom" wrote:
Yes, it resides in the center, you can note this during a defrag (especially
good defragging programs). The link I gave you said specifically that it
resides there. "A duplicate of the boot sector is located at the logical
center of the disk."

Here is an example snapshot of a defrag analysis (hope you have high speed
internet), and note the color legend regarding the MFTs to the color scheme
in the main window.

http://home.insightbb.com/~guesswho192/MFT_example.JPG


If the MFT must be in the middle of a partition or the middle of a disk,
it seems you're pointing out a problem of access by the BIOS of MFTs
in drives larger than, say 2x137GB. But all the BIOS does is load the
code in the Master Boot Record, which is at the bottom of the HD's
address space, and that executable code, using the partition table,
finds and loads ntldr. It would seem that the BIOS really doesn't have
to access anything higher than cylinder 0 on the disk.

*TimDaniels*

"Timothy Daniels" wrote in message
...
"Tom" wrote:
Yes, it resides in the center, you can note this during a defrag
(especially good defragging programs). The link I gave you said
specifically that it resides there. "A duplicate of the boot sector is
located at the logical center of the disk."

Here is an example snapshot of a defrag analysis (hope you have high
speed internet), and note the color legend regarding the MFTs to the
color scheme in the main window.

http://home.insightbb.com/~guesswho192/MFT_example.JPG


If the MFT must be in the middle of a partition or the middle of a disk,
it seems you're pointing out a problem of access by the BIOS of MFTs
in drives larger than, say 2x137GB. But all the BIOS does is load the
code in the Master Boot Record, which is at the bottom of the HD's
address space, and that executable code, using the partition table,
finds and loads ntldr. It would seem that the BIOS really doesn't have
to access anything higher than cylinder 0 on the disk.

*TimDaniels*


I am not pointing out any problems, this is simply how this functions in
NTFS formatted partitions

The BIOS only loads to what is designated the first boot device, after that,
it is up to the device to begin loading through the MBR. MBR and the MFT
have little to do with each other, and how the BIOS recognizes listings.

"Tom" wrote:

"Timothy Daniels" wrote:
"Tom" wrote:
Yes, it resides in the center, you can note this during a defrag
(especially good defragging programs). The link I gave you said
specifically that it resides there. "A duplicate of the boot sector is
located at the logical center of the disk."

Here is an example snapshot of a defrag analysis (hope you have high
speed internet), and note the color legend regarding the MFTs to the
color scheme in the main window.

http://home.insightbb.com/~guesswho192/MFT_example.JPG


If the MFT must be in the middle of a partition or the middle of a disk,
it seems you're pointing out a problem of access by the BIOS of MFTs
in drives larger than, say 2x137GB. But all the BIOS does is load the
code in the Master Boot Record, which is at the bottom of the HD's
address space, and that executable code, using the partition table,
finds and loads ntldr. It would seem that the BIOS really doesn't have
to access anything higher than cylinder 0 on the disk.

*TimDaniels*


I am not pointing out any problems, this is simply how this functions in
NTFS formatted partitions

The BIOS only loads to what is designated the first boot device, after that,
it is up to the device to begin loading through the MBR. MBR and the MFT
have little to do with each other, and how the BIOS recognizes listings.


Then I have no idea what your point is.

*TimDaniels*

"Timothy Daniels" wrote in message
...
"Tom" wrote:

"Timothy Daniels" wrote:
"Tom" wrote:
Yes, it resides in the center, you can note this during a defrag
(especially good defragging programs). The link I gave you said
specifically that it resides there. "A duplicate of the boot sector is
located at the logical center of the disk."

Here is an example snapshot of a defrag analysis (hope you have high
speed internet), and note the color legend regarding the MFTs to the
color scheme in the main window.

http://home.insightbb.com/~guesswho192/MFT_example.JPG


If the MFT must be in the middle of a partition or the middle of a disk,
it seems you're pointing out a problem of access by the BIOS of MFTs
in drives larger than, say 2x137GB. But all the BIOS does is load the
code in the Master Boot Record, which is at the bottom of the HD's
address space, and that executable code, using the partition table,
finds and loads ntldr. It would seem that the BIOS really doesn't have
to access anything higher than cylinder 0 on the disk.

*TimDaniels*


I am not pointing out any problems, this is simply how this functions in
NTFS formatted partitions

The BIOS only loads to what is designated the first boot device, after
that, it is up to the device to begin loading through the MBR. MBR and
the MFT have little to do with each other, and how the BIOS recognizes
listings.


Then I have no idea what your point is.



Wow, then maybe you should refrain from this topic. Read what a BIOS is, and
its function, then read about the MBR, and an MFT, and you'll see they have
nothing to do with the BIOS. You're the one who said, "seems you're pointing
out a problem of access by the BIOS of MFTs in drives larger than, say
2x137GB. But all the BIOS does is load the code in the Master Boot Record"

I said nothing regarding the BIOS, you brought that up, hence my reply. I
answered you solely regarding your query regarding the MFT, and it location
on the physical drive. How you *seem* to have had me make some allusion to
the BIOS, is something totally conjured up in your mind. If you are
concerned about what Andy stated regarding his mention of the BIOS and MFTs,
then ask him what he meant. I simply started with this particular part of
the thread, answering a question you posited regarding the location of the
MFT.