Active or logical partition

This is really strange. I have 3 drives on my system, and they all have an
active partition, and I boot to three different Operating Systems, with no
issues.
From Disk Management in Vista x64 which I am running at the moment.

Volume | Layout | Type | File System | Status
Simple Basic
Healthy (Active, Primary Partition) "Fedora 7 boot partiton" IDE 1
Simple Basic
Healthy (Primary Partition) "Fedora 7 System" IDE 1
Programs and Files (G Simple Basic NTFS Healthy (Logical
Drive) "Partitioned from XP Drive" Sata2
TRA (D Simple Basic CDFS Healthy
(Primary Partition) "DVD writer with dvd in it."
Vista 64 (C Simple Basic NTFS Healthy
(System, Boot, PageFile,Active, Crash Dump, Primary Partition) "Vista" Sata1
Win XP 32 bit (F Simple Basic NTFS Healthy
(Active, Primary Partition) Sata2

When XP is the OS, the drives look different
Win XP is C: ; Prog.... is Drive D: DVD writers are E and F, and the Vista
Drive becomes G:

So it looks like it is possible to have more than one Active partition on a
system.

"R. C. White" <> wrote in message
news:25B7DFF3-9115-4881-95C4-...
> Hi, John.
>
> I agree with your disagreement. KB 314470 was rewritten just last month
> to apply to Vista, as well as earlier Windows versions. I'll let them
> know that it needs still another revision.
>
> As you suggest, Vista does not require these 3 files at all unless it is
> dual-booting WinXP/2K/NT as well. The names of those 3 files did not
> change from WinNT4 (at least - that's where I started with NT) to WinXP,
> but the content of NTLDR and NTDETECT.COM grew with each new version of
> the operating system, partly because each version needed to know how to
> boot all the predecessor versions. Even in the SP2 version of WinXP,
> those files are larger and dated later than in the original WinXP. And
> the WinXP x64 versions are still larger; maybe that's what made the
> article writer think that the files were "hardware-specific", since the
> x64 versions were larger than the x86 versions.
>
> For Vista, the files that must be in the Root of the System Partition are
> bootmgr (no extension) and the \Boot folder.
>
> Thanks for pointing out the error, John.
>
> RC
> --
> R. C. White, CPA
> San Marcos, TX
>
> Microsoft Windows MVP
> (Running Windows Live Mail beta in Vista Ultimate x64)
>
> "John Barnes" <> wrote in message
> news:...
>> Personally I don't agree with the definitions given in your link.
>> Doesn't agree with most of Microsoft published material.
>> for instance hardware-specific files that are needed to start Windows,
>> such as Ntldr, Boot.ini, and Ntdetect.com
>> should read software specific as this is for legacy nt booting OS's
>> (software) and has nothing to do with hardware.
>>
>> "R. C. White" <> wrote in message
>> news:FFC200D5-858B-409D-8EAE-...
>>> Hi, Paul.
>>>
>>> Excellent post. One small quibble:
>>>> primary partitions, you can have one extended partition. That extended
>>>> partition can be chopped into many partitions.
>>>
>>> The extended partition can be chopped into many logical drives.
>>>
>>> Each primary partition and each logical drive can be assigned a "drive"
>>> letter and separately formatted. The extended partition does not get a
>>> drive letter and cannot be formatted as a unit.
>>>
>>> The TechNet article you quoted from is dated 1999, before Vista or WinXP
>>> or even Win2K, but most of it is still applicable today. Just shows
>>> that a few hours spent studying the basic structure of hard disks will
>>> continue to pay dividends through several generations of Windows. ;<)
>>>
>>> And to Paul Costanza, the OP, no matter how many Windows installations
>>> you have, the boot process will always start in the System Partition
>>> (usually the first primary partition on the first hard drive - but not
>>> always) and then branch to the boot volume (primary partition or logical
>>> drive holding the \Windows folder) for whichever Windows installation
>>> you select from the opening menu - and that opening menu is one of the
>>> things store in the System Partition. So I like to have a single
>>> primary partition on the first HD to serve as the System Partition, plus
>>> multiple logical drives - on multiple hard drives - to serve as boot
>>> volumes for my multiple operating systems.
>>>
>>> As some writers have commented, "Those not sophisticated about such
>>> matters may think it strange that we boot from the system partition and
>>> keep our operating system files in the boot volume." But that's the way
>>> it has always been. You might want to check out this KB article:
>>> Definitions for system volume and boot volume
>>> http://support.microsoft.com/default.../314470/EN-US/
>>>
>>> RC
>>> --
>>> R. C. White, CPA
>>> San Marcos, TX
>>>
>>> Microsoft Windows MVP
>>> (Running Windows Live Mail beta in Vista Ultimate x64)
>>>
>>> "Paul Randall" <> wrote in message
>>> news:...
>>>>I don't agree completely with the other answers you have gotten so far.
>>>> This part of your question "but don't know if that second hard drive
>>>> for Vista should be set as active or logical" indicates you don't quite
>>>> understand the terminology enough to understand partitioning.
>>>>
>>>> At first it is kind of difficult to understand the difference between a
>>>> physical hard drive and the various uses for the word "drive" when
>>>> talking about drives. A drive letter never refers to the physical hard
>>>> drive - it always refers to a partition on a hard drive or memory card
>>>> or thumb drive or whatever.
>>>>
>>>> A brand new hard drive typically has zeros in every byte of every
>>>> sector. Prior to using the drive, you must initialize and partition it
>>>> (perhaps partitioning is initializing - I'm not sure). Windows can do
>>>> this from the instalation CD/DVD or under disc management within
>>>> windows XP or Vista. Physical drives are not 'set active' -- 'active'
>>>> is a property of a primary partition. Only one Primary partition
>>>> should be active at one time. The active partition is the one that the
>>>> system will try to boot from. Primary partitions can be hidden or not
>>>> hidden. For primary partitions, only non-hidden ones are assigned drive
>>>> letters. (If you have less than four primary partitions, you can have
>>>> one extended partition. That extended partition can be chopped into
>>>> many partitions.
>>>>
>>>> Following is come info I copied from here:
>>>> http://www.microsoft.com/technet/arc....mspx?mfr=true
>>>> Most references to NT apply to WXP and Vista too.
>>>> <Quote>
>>>> Okay, let's do a short review. The Master Boot Record (MBR) on each
>>>> hard disk contains the Partition Table, and the computer uses the
>>>> partition table to determine how to access the disk. There is room in
>>>> the partition table for four entries, called (not surprisingly)
>>>> partitions. A partition is a portion of a hard disk that is set up to
>>>> act like a separate physical hard disk. A partition must be completely
>>>> contained on one physical hard disk. The MBR understands two types of
>>>> partitions: primary and extended.
>>>> A primary partition is a portion of a physical hard disk marked as
>>>> bootable by NT, is formatted with a particular file system, and is
>>>> assigned a drive letter. With NT, there can be multiple partitions on a
>>>> drive, of which one at a time can be marked "active", meaning that you
>>>> can boot from it.
>>>>
>>>> An extended partition is effectively a logical disk and can be
>>>> subdivided into smaller logical drives. You can have only one extended
>>>> partition per hard disk.
>>>>
>>>> The "System Partition" is the partition that contains the hardware
>>>> specific files used in loading and initializing the operating system.
>>>> Only a primary partition can be used as a system partition. Windows NT
>>>> actually requires that the system partition be a primary partition.
>>>>
>>>> Then there's the Boot Partition. The boot partition is also used in
>>>> starting the operating system and contains the operating system files
>>>> needed by the OS. Both a primary partition and a logical drive in an
>>>> extended partition can be used as a boot partition.
>>>> </Quote>
>>>>
>>>> Try skimming this URL and then read the parts that seem to apply to
>>>> your situation:
>>>>
>>>> http://www.ata-atapi.com/hiwtab.htm
>>>>
>>>> -Paul Randall
>>>>
>>>> "Paul" <> wrote in message
>>>> news:AB07A346-8D8F-44F3-B00B-...
>>>>> If I'm setting up XP and Vista on separate drives for dual boot, do I
>>>>> make both drives active? I've installed XP already and will be
>>>>> installing Vista on the second hard drive but don't know if that
>>>>> second hard drive for Vista should be set as active or logical.
>>>
>>

You can have one active primary partition per hard drive with no problems.

"Cesar Ventura" <> wrote in message
news:...
> This is really strange. I have 3 drives on my system, and they all have
> an active partition, and I boot to three different Operating Systems, with
> no issues.
> From Disk Management in Vista x64 which I am running at the moment.
>
> Volume | Layout | Type | File System | Status
> Simple Basic Healthy (Active,
> Primary Partition) "Fedora 7 boot partiton" IDE 1
> Simple Basic Healthy (Primary
> Partition) "Fedora 7 System" IDE 1
> Programs and Files (G Simple Basic NTFS Healthy
> (Logical Drive) "Partitioned from XP Drive" Sata2
> TRA (D Simple Basic CDFS Healthy
> (Primary Partition) "DVD writer with dvd in it."
> Vista 64 (C Simple Basic NTFS Healthy
> (System, Boot, PageFile,Active, Crash Dump, Primary Partition) "Vista"
> Sata1
> Win XP 32 bit (F Simple Basic NTFS Healthy
> (Active, Primary Partition) Sata2
>
> When XP is the OS, the drives look different
> Win XP is C: ; Prog.... is Drive D: DVD writers are E and F, and the
> Vista Drive becomes G:
>
> So it looks like it is possible to have more than one Active partition on
> a system.
>
> "R. C. White" <> wrote in message
> news:25B7DFF3-9115-4881-95C4-...
>> Hi, John.
>>
>> I agree with your disagreement. KB 314470 was rewritten just last month
>> to apply to Vista, as well as earlier Windows versions. I'll let them
>> know that it needs still another revision.
>>
>> As you suggest, Vista does not require these 3 files at all unless it is
>> dual-booting WinXP/2K/NT as well. The names of those 3 files did not
>> change from WinNT4 (at least - that's where I started with NT) to WinXP,
>> but the content of NTLDR and NTDETECT.COM grew with each new version of
>> the operating system, partly because each version needed to know how to
>> boot all the predecessor versions. Even in the SP2 version of WinXP,
>> those files are larger and dated later than in the original WinXP. And
>> the WinXP x64 versions are still larger; maybe that's what made the
>> article writer think that the files were "hardware-specific", since the
>> x64 versions were larger than the x86 versions.
>>
>> For Vista, the files that must be in the Root of the System Partition are
>> bootmgr (no extension) and the \Boot folder.
>>
>> Thanks for pointing out the error, John.
>>
>> RC
>> --
>> R. C. White, CPA
>> San Marcos, TX
>>
>> Microsoft Windows MVP
>> (Running Windows Live Mail beta in Vista Ultimate x64)
>>
>> "John Barnes" <> wrote in message
>> news:...
>>> Personally I don't agree with the definitions given in your link.
>>> Doesn't agree with most of Microsoft published material.
>>> for instance hardware-specific files that are needed to start Windows,
>>> such as Ntldr, Boot.ini, and Ntdetect.com
>>> should read software specific as this is for legacy nt booting OS's
>>> (software) and has nothing to do with hardware.
>>>
>>> "R. C. White" <> wrote in message
>>> news:FFC200D5-858B-409D-8EAE-...
>>>> Hi, Paul.
>>>>
>>>> Excellent post. One small quibble:
>>>>> primary partitions, you can have one extended partition. That
>>>>> extended partition can be chopped into many partitions.
>>>>
>>>> The extended partition can be chopped into many logical drives.
>>>>
>>>> Each primary partition and each logical drive can be assigned a "drive"
>>>> letter and separately formatted. The extended partition does not get a
>>>> drive letter and cannot be formatted as a unit.
>>>>
>>>> The TechNet article you quoted from is dated 1999, before Vista or
>>>> WinXP or even Win2K, but most of it is still applicable today. Just
>>>> shows that a few hours spent studying the basic structure of hard disks
>>>> will continue to pay dividends through several generations of Windows.
>>>> ;<)
>>>>
>>>> And to Paul Costanza, the OP, no matter how many Windows installations
>>>> you have, the boot process will always start in the System Partition
>>>> (usually the first primary partition on the first hard drive - but not
>>>> always) and then branch to the boot volume (primary partition or
>>>> logical drive holding the \Windows folder) for whichever Windows
>>>> installation you select from the opening menu - and that opening menu
>>>> is one of the things store in the System Partition. So I like to have
>>>> a single primary partition on the first HD to serve as the System
>>>> Partition, plus multiple logical drives - on multiple hard drives - to
>>>> serve as boot volumes for my multiple operating systems.
>>>>
>>>> As some writers have commented, "Those not sophisticated about such
>>>> matters may think it strange that we boot from the system partition and
>>>> keep our operating system files in the boot volume." But that's the
>>>> way it has always been. You might want to check out this KB article:
>>>> Definitions for system volume and boot volume
>>>> http://support.microsoft.com/default.../314470/EN-US/
>>>>
>>>> RC
>>>> --
>>>> R. C. White, CPA
>>>> San Marcos, TX
>>>>
>>>> Microsoft Windows MVP
>>>> (Running Windows Live Mail beta in Vista Ultimate x64)
>>>>
>>>> "Paul Randall" <> wrote in message
>>>> news:...
>>>>>I don't agree completely with the other answers you have gotten so far.
>>>>> This part of your question "but don't know if that second hard drive
>>>>> for Vista should be set as active or logical" indicates you don't
>>>>> quite understand the terminology enough to understand partitioning.
>>>>>
>>>>> At first it is kind of difficult to understand the difference between
>>>>> a physical hard drive and the various uses for the word "drive" when
>>>>> talking about drives. A drive letter never refers to the physical
>>>>> hard drive - it always refers to a partition on a hard drive or memory
>>>>> card or thumb drive or whatever.
>>>>>
>>>>> A brand new hard drive typically has zeros in every byte of every
>>>>> sector. Prior to using the drive, you must initialize and partition it
>>>>> (perhaps partitioning is initializing - I'm not sure). Windows can do
>>>>> this from the instalation CD/DVD or under disc management within
>>>>> windows XP or Vista. Physical drives are not 'set active' -- 'active'
>>>>> is a property of a primary partition. Only one Primary partition
>>>>> should be active at one time. The active partition is the one that
>>>>> the system will try to boot from. Primary partitions can be hidden or
>>>>> not hidden. For primary partitions, only non-hidden ones are assigned
>>>>> drive letters. (If you have less than four primary partitions, you can
>>>>> have one extended partition. That extended partition can be chopped
>>>>> into many partitions.
>>>>>
>>>>> Following is come info I copied from here:
>>>>> http://www.microsoft.com/technet/arc....mspx?mfr=true
>>>>> Most references to NT apply to WXP and Vista too.
>>>>> <Quote>
>>>>> Okay, let's do a short review. The Master Boot Record (MBR) on each
>>>>> hard disk contains the Partition Table, and the computer uses the
>>>>> partition table to determine how to access the disk. There is room in
>>>>> the partition table for four entries, called (not surprisingly)
>>>>> partitions. A partition is a portion of a hard disk that is set up to
>>>>> act like a separate physical hard disk. A partition must be completely
>>>>> contained on one physical hard disk. The MBR understands two types of
>>>>> partitions: primary and extended.
>>>>> A primary partition is a portion of a physical hard disk marked as
>>>>> bootable by NT, is formatted with a particular file system, and is
>>>>> assigned a drive letter. With NT, there can be multiple partitions on
>>>>> a drive, of which one at a time can be marked "active", meaning that
>>>>> you can boot from it.
>>>>>
>>>>> An extended partition is effectively a logical disk and can be
>>>>> subdivided into smaller logical drives. You can have only one extended
>>>>> partition per hard disk.
>>>>>
>>>>> The "System Partition" is the partition that contains the hardware
>>>>> specific files used in loading and initializing the operating system.
>>>>> Only a primary partition can be used as a system partition. Windows NT
>>>>> actually requires that the system partition be a primary partition.
>>>>>
>>>>> Then there's the Boot Partition. The boot partition is also used in
>>>>> starting the operating system and contains the operating system files
>>>>> needed by the OS. Both a primary partition and a logical drive in an
>>>>> extended partition can be used as a boot partition.
>>>>> </Quote>
>>>>>
>>>>> Try skimming this URL and then read the parts that seem to apply to
>>>>> your situation:
>>>>>
>>>>> http://www.ata-atapi.com/hiwtab.htm
>>>>>
>>>>> -Paul Randall
>>>>>
>>>>> "Paul" <> wrote in message
>>>>> news:AB07A346-8D8F-44F3-B00B-...
>>>>>> If I'm setting up XP and Vista on separate drives for dual boot, do I
>>>>>> make both drives active? I've installed XP already and will be
>>>>>> installing Vista on the second hard drive but don't know if that
>>>>>> second hard drive for Vista should be set as active or logical.
>>>>
>>>
>

Hi, Cesar.

> So it looks like it is possible to have more than one Active partition on
> a system.

Yes. As John says, we can have one active partition on each physical hard
disk drive. I haven't run a non-Windows OS since trying OS/2 Warp when it
was new. But each of my 3 physical drives has a primary partition, and I've
installed Vista with each of them, in turn, serving as the boot device. So
now I can designate any one of them the current boot device and boot into
Vista. I consider that good insurance in case my current favorite drive
dies on me. And it has paid off in the past!

(Actually, I'm exaggerating a little. I have had such a complete
arrangement in the past, but I've been sloppy about updating it. At one
point during the Vista beta, I was multi-booting both 32-bit and 64-bit
versions of WinXP and of 3 Vista builds, eight operating systems at once.
And my hardware has evolved, too; currently I have 4 physical drives, but 2
are treated as a single RAID 1, so I have 3 active primary partitions.
Since installing Vista RTM on my new mobo/CPU last December, I've seldom
booted into anything else and I'm not sure I could right now. I need to do
some maintenance - but Vista is running so well that I keep putting it off.)

WLM messed up the formatting of your Disk Management details, of course, but
this is the key line:
> Vista 64 (C Simple Basic NTFS Healthy
> (System, Boot, PageFile,Active, Crash Dump, Primary Partition) "Vista"
> Sata1

When you are in Vista x64, this partition will be both the System Partition
and the Boot Volume, and Vista will see it as Drive C:. But if you reboot
from the same physical drive into WinXP, this same partition will still be
the System Partition, but it will not be the Boot Volume for WinXP, and it
might not be Drive C:. As you describe your system, you probably will
switch your BIOS (temporarily or semi-permanently) to boot from your SATA 2
when you want to run WinXP. In that case, the active primary partition on
SATA 2 will become the System Partition and WinXP's Boot Volume. Vista sees
that volume as Drive F:, but WinXP will see it as Drive C: - and WinXP has
assigned the first partition on SATA 1, which Vista sees as Drive C:, the
letter G:.

This multi-booting gets very exciting - and confusing. Especially when
there are multiple physical drives. Each physical drive can have up to 4
primary partitions, and any one of them at a time may be marked Active, and
a different one can be set active before the next reboot. Most users don't
know or care about all this. For those who do, the Disk Management Help
file has a lot of good information, but it is arranged as a reference, not a
text, so there's a lot of jumping around to find the information.

RC
--
R. C. White, CPA
San Marcos, TX

Microsoft Windows MVP
(Running Windows Live Mail beta in Vista Ultimate x64)

"Cesar Ventura" <> wrote in message
news:...
> This is really strange. I have 3 drives on my system, and they all have
> an active partition, and I boot to three different Operating Systems, with
> no issues.
> From Disk Management in Vista x64 which I am running at the moment.
>
> Volume | Layout | Type | File System | Status
> Simple Basic Healthy (Active,
> Primary Partition) "Fedora 7 boot partiton" IDE 1
> Simple Basic Healthy (Primary
> Partition) "Fedora 7 System" IDE 1
> Programs and Files (G Simple Basic NTFS Healthy
> (Logical Drive) "Partitioned from XP Drive" Sata2
> TRA (D Simple Basic CDFS Healthy
> (Primary Partition) "DVD writer with dvd in it."
> Vista 64 (C Simple Basic NTFS Healthy
> (System, Boot, PageFile,Active, Crash Dump, Primary Partition) "Vista"
> Sata1
> Win XP 32 bit (F Simple Basic NTFS Healthy
> (Active, Primary Partition) Sata2
>
> When XP is the OS, the drives look different
> Win XP is C: ; Prog.... is Drive D: DVD writers are E and F, and the
> Vista Drive becomes G:
>
> So it looks like it is possible to have more than one Active partition on
> a system.
>
> "R. C. White" <> wrote in message
> news:25B7DFF3-9115-4881-95C4-...
>> Hi, John.
>>
>> I agree with your disagreement. KB 314470 was rewritten just last month
>> to apply to Vista, as well as earlier Windows versions. I'll let them
>> know that it needs still another revision.
>>
>> As you suggest, Vista does not require these 3 files at all unless it is
>> dual-booting WinXP/2K/NT as well. The names of those 3 files did not
>> change from WinNT4 (at least - that's where I started with NT) to WinXP,
>> but the content of NTLDR and NTDETECT.COM grew with each new version of
>> the operating system, partly because each version needed to know how to
>> boot all the predecessor versions. Even in the SP2 version of WinXP,
>> those files are larger and dated later than in the original WinXP. And
>> the WinXP x64 versions are still larger; maybe that's what made the
>> article writer think that the files were "hardware-specific", since the
>> x64 versions were larger than the x86 versions.
>>
>> For Vista, the files that must be in the Root of the System Partition are
>> bootmgr (no extension) and the \Boot folder.
>>
>> Thanks for pointing out the error, John.
>>
>> RC
>>
>> "John Barnes" <> wrote in message
>> news:...
>>> Personally I don't agree with the definitions given in your link.
>>> Doesn't agree with most of Microsoft published material.
>>> for instance hardware-specific files that are needed to start Windows,
>>> such as Ntldr, Boot.ini, and Ntdetect.com
>>> should read software specific as this is for legacy nt booting OS's
>>> (software) and has nothing to do with hardware.
>>>
>>> "R. C. White" <> wrote in message
>>> news:FFC200D5-858B-409D-8EAE-...
>>>> Hi, Paul.
>>>>
>>>> Excellent post. One small quibble:
>>>>> primary partitions, you can have one extended partition. That
>>>>> extended partition can be chopped into many partitions.
>>>>
>>>> The extended partition can be chopped into many logical drives.
>>>>
>>>> Each primary partition and each logical drive can be assigned a "drive"
>>>> letter and separately formatted. The extended partition does not get a
>>>> drive letter and cannot be formatted as a unit.
>>>>
>>>> The TechNet article you quoted from is dated 1999, before Vista or
>>>> WinXP or even Win2K, but most of it is still applicable today. Just
>>>> shows that a few hours spent studying the basic structure of hard disks
>>>> will continue to pay dividends through several generations of Windows.
>>>> ;<)
>>>>
>>>> And to Paul Costanza, the OP, no matter how many Windows installations
>>>> you have, the boot process will always start in the System Partition
>>>> (usually the first primary partition on the first hard drive - but not
>>>> always) and then branch to the boot volume (primary partition or
>>>> logical drive holding the \Windows folder) for whichever Windows
>>>> installation you select from the opening menu - and that opening menu
>>>> is one of the things store in the System Partition. So I like to have
>>>> a single primary partition on the first HD to serve as the System
>>>> Partition, plus multiple logical drives - on multiple hard drives - to
>>>> serve as boot volumes for my multiple operating systems.
>>>>
>>>> As some writers have commented, "Those not sophisticated about such
>>>> matters may think it strange that we boot from the system partition and
>>>> keep our operating system files in the boot volume." But that's the
>>>> way it has always been. You might want to check out this KB article:
>>>> Definitions for system volume and boot volume
>>>> http://support.microsoft.com/default.../314470/EN-US/
>>>>
>>>> RC
>>>>
>>>> "Paul Randall" <> wrote in message
>>>> news:...
>>>>>I don't agree completely with the other answers you have gotten so far.
>>>>> This part of your question "but don't know if that second hard drive
>>>>> for Vista should be set as active or logical" indicates you don't
>>>>> quite understand the terminology enough to understand partitioning.
>>>>>
>>>>> At first it is kind of difficult to understand the difference between
>>>>> a physical hard drive and the various uses for the word "drive" when
>>>>> talking about drives. A drive letter never refers to the physical
>>>>> hard drive - it always refers to a partition on a hard drive or memory
>>>>> card or thumb drive or whatever.
>>>>>
>>>>> A brand new hard drive typically has zeros in every byte of every
>>>>> sector. Prior to using the drive, you must initialize and partition it
>>>>> (perhaps partitioning is initializing - I'm not sure). Windows can do
>>>>> this from the instalation CD/DVD or under disc management within
>>>>> windows XP or Vista. Physical drives are not 'set active' -- 'active'
>>>>> is a property of a primary partition. Only one Primary partition
>>>>> should be active at one time. The active partition is the one that
>>>>> the system will try to boot from. Primary partitions can be hidden or
>>>>> not hidden. For primary partitions, only non-hidden ones are assigned
>>>>> drive letters. (If you have less than four primary partitions, you can
>>>>> have one extended partition. That extended partition can be chopped
>>>>> into many partitions.
>>>>>
>>>>> Following is come info I copied from here:
>>>>> http://www.microsoft.com/technet/arc....mspx?mfr=true
>>>>> Most references to NT apply to WXP and Vista too.
>>>>> <Quote>
>>>>> Okay, let's do a short review. The Master Boot Record (MBR) on each
>>>>> hard disk contains the Partition Table, and the computer uses the
>>>>> partition table to determine how to access the disk. There is room in
>>>>> the partition table for four entries, called (not surprisingly)
>>>>> partitions. A partition is a portion of a hard disk that is set up to
>>>>> act like a separate physical hard disk. A partition must be completely
>>>>> contained on one physical hard disk. The MBR understands two types of
>>>>> partitions: primary and extended.
>>>>> A primary partition is a portion of a physical hard disk marked as
>>>>> bootable by NT, is formatted with a particular file system, and is
>>>>> assigned a drive letter. With NT, there can be multiple partitions on
>>>>> a drive, of which one at a time can be marked "active", meaning that
>>>>> you can boot from it.
>>>>>
>>>>> An extended partition is effectively a logical disk and can be
>>>>> subdivided into smaller logical drives. You can have only one extended
>>>>> partition per hard disk.
>>>>>
>>>>> The "System Partition" is the partition that contains the hardware
>>>>> specific files used in loading and initializing the operating system.
>>>>> Only a primary partition can be used as a system partition. Windows NT
>>>>> actually requires that the system partition be a primary partition.
>>>>>
>>>>> Then there's the Boot Partition. The boot partition is also used in
>>>>> starting the operating system and contains the operating system files
>>>>> needed by the OS. Both a primary partition and a logical drive in an
>>>>> extended partition can be used as a boot partition.
>>>>> </Quote>
>>>>>
>>>>> Try skimming this URL and then read the parts that seem to apply to
>>>>> your situation:
>>>>>
>>>>> http://www.ata-atapi.com/hiwtab.htm
>>>>>
>>>>> -Paul Randall
>>>>>
>>>>> "Paul" <> wrote in message
>>>>> news:AB07A346-8D8F-44F3-B00B-...
>>>>>> If I'm setting up XP and Vista on separate drives for dual boot, do I
>>>>>> make both drives active? I've installed XP already and will be
>>>>>> installing Vista on the second hard drive but don't know if that
>>>>>> second hard drive for Vista should be set as active or logical.