12yGB Drive Limitation

[mcp6453]

System is a P4 using Window XP Pro with SP2 and a Promise ATA100
controller card. There is a 250 GB drive for data only. It has worked
for a long time as a 250 GB drive. Customer tried to reformat the drive
and can only get it to format as a 127 GB drive. The BIOS sees the drive
as 250 GB. What's the problem?

 

[Rod Speed]

System is a P4 using Window XP Pro with SP2 and a Promise ATA100 controller
card. There is a 250 GB drive for data only. It has worked for a long time as
a 250 GB drive.

In that config ?

Customer tried to reformat the drive

Using what ?

and can only get it to format as a 127 GB drive. The BIOS sees the drive as
250 GB. What's the problem?

Likely the bios is just reporting what the drive itself
says it has space wise. Whatever is being used to
format the drive likely doesnt allow for 48bit LBA.

XP SP2 does allow for 48bit LBA so it would be best
to use XP Disk Management to format the drive.

If that is what is being used, likely you have somehow
got the basic drive geometry details in the MBR wrong,
using say XP without even SP1 applied to partition it
or something and then kludged your way around that.

Best to wipe the drive completely using something
like clearhdd and then partition and format it again
using just the XP Disk Management.

 

[mcp6453]

In that config ?

The OS is on a smaller drive and is working fine.

Using what ?

XP Disk Management

Likely the bios is just reporting what the drive itself
says it has space wise. Whatever is being used to
format the drive likely doesnt allow for 48bit LBA.

XP SP2 does allow for 48bit LBA so it would be best
to use XP Disk Management to format the drive.

If that is what is being used, likely you have somehow
got the basic drive geometry details in the MBR wrong,
using say XP without even SP1 applied to partition it
or something and then kludged your way around that.

Best to wipe the drive completely using something
like clearhdd and then partition and format it again
using just the XP Disk Management.

Are you saying that the MBR is hosed? I can wipe it with Terabyte
Unlimited's BootItNG. I had not thought about that. I'm not familiar
with clearhdd, but I'm getting ready to look it up.

 

[Michael Kimmer]

System is a P4 using Window XP Pro with SP2 and a Promise ATA100
controller card. There is a 250 GB drive for data only. It has worked
for a long time as a 250 GB drive. Customer tried to reformat the
drive and can only get it to format as a 127 GB drive. The BIOS sees
the drive as 250 GB. What's the problem?

You can find the solution here:
http://support.microsoft.com/default.aspx?scid=kb;en-us;303013

--
M.f.G.
Michael Kimmer

"Ein Tag an dem Du nicht lächelst ist ein verlorener Tag"
"Eine Nacht in der Du nicht schläfst ist eine verschlafene Nacht"

 

[Rod Speed]

Rod Speed wrote

The OS is on a smaller drive and is working fine.

I meant was it always used in that config ?

If the 250G drive wasnt always on the Promise card,
thats most likely why it cant be formatted to 250G now.

XP Disk Management

Are you saying that the MBR is hosed?

Dunno, its more likely the problem is the Promise card bios
not supporting 48 bit LBA if it was orignally formatted on the
motherboard IDE controller and you cant reformat it now.

Presumably the bios on the Promise card can
be updated to include 48bit LBA support now.

I can wipe it with Terabyte Unlimited's BootItNG. I had not thought about
that. I'm not familiar with clearhdd, but I'm getting ready to look it up.

Not 100% sure it can wipe a drive on the Promise card.
Tad risky too, it uses a drive number system to specify
which drive to wipe and thats a tad risky in that situation.
I'd use BootItNG instead if you are sure it can wipe the
drive, or physically unplug the boot drive when using
clearhdd so you cant wipe it by accident.

Its not likely to help tho if you originally formatted the
250G on the motherboard IDE controller, the problem
is likely to be the Promise bios not supporting 48bit LBA.
MS says that the bios has to support 48bit LBA but they
dont say why thats important, they just proclaim that.

 

[Folkert Rienstra]

MS says that the bios has to support 48bit LBA but they

dont say why thats important, they just proclaim that.

Presumably because diskmanagement still uses BIOS.

 

[Rod Speed]

Presumably because diskmanagement still uses BIOS.

Dunno, it must be more complicated than that when
it handles drives that arent visible to the bios fine.

Presumably it only matters in some situations and
they havent bothered to spell out the detail on that.

 

[Folkert Rienstra]

Dunno, it must be more complicated than that when
it handles drives that arent visible to the bios fine.

Maybe that's because the Windows driver will substitute it's own bios
calls whereas with the bios available it will use that, limited and all.

Presumably it only matters in some situations and
they havent bothered to spell out the detail on that.

Yup.
And diskmanagement using BIOS is the most likely candidate.
One reason they may not wanna talk about it is that some ver-
sions of Windows Install will wipe out an installed overlay.

[snip]

 

[Rod Speed]

Maybe that's because the Windows driver will substitute it's own bios
calls whereas with the bios available it will use that, limited and all.

Must be more complicated than that too when
it is actually possible to get 48bit LBA working
properly when the bios doesnt support that.

Yup.
And diskmanagement using BIOS is the most likely candidate.
One reason they may not wanna talk about it is that some
versions of Windows Install will wipe out an installed overlay.

What has that got to do with 48bit LBA support in the bios ?

[snip]

 

[Folkert Rienstra]

To be clear, the Windows driver doesn't use the bios calls, it will only
offer them for applications to use.

Must be more complicated than that too when
it is actually possible to get 48-bit LBA working
properly when the bios doesnt support that.

It is common knowledge that it isn't using BIOS, it is using drivers.
What's not so common knowledge is that diskmanagement isn't using
drivers but BIOS. If BIOS isn't available, diskmanagement can use
the driver supplied BIOS calls.

What has that got to do with 48-bit LBA support in the bios ?

Everything, obviously.
In order to be able to partition a 'large' drive one needs 48-bit
LBA support in the BIOS, either supplied by the bios setup itself
or a BIOS substitute/enhancement like a drive overlay software.
However some Windows installations wipe/deactivate the drive
overlay software and that can possibly disrupt the Windows install.
It may be easier for MS to avoid this whole situation by saying that
you need original 48-bit LBA BIOS support.

Rod Speed wrote
mcp6453 <[email protected]> wrote

[snip]

 

[Rod Speed]

To be clear, the Windows driver doesn't use the bios
calls, it will only offer them for applications to use.

Thats rather mangled.

It is common knowledge that it isn't using BIOS, it is
using drivers. What's not so common knowledge is
that diskmanagement isn't using drivers but BIOS.

Its more complicated than that, most obviously with drives
that arent found by the bios but are by the Win drivers.

If BIOS isn't available, diskmanagement
can use the driver supplied BIOS calls.

Everything, obviously.

We'll see.

In order to be able to partition a 'large' drive one needs 48-bit
LBA support in the BIOS, either supplied by the bios setup itself
or a BIOS substitute/enhancement like a drive overlay software.

That is just plain wrong.

However some Windows installations wipe/deactivate the drive
overlay software and that can possibly disrupt the Windows install.

You dont need to have drive overlay software with non boot drives.

It may be easier for MS to avoid this whole situation by
saying that you need original 48-bit LBA BIOS support.

Still cant fly with non boot drives.

Rod Speed wrote

[snip]