Largest partition size in XP

Tristan · 09-07-2004, 23:40

Can anybody tell me the largest HD partition size supported by Windows XP? I'm planning on buying a couple of 120GB disks for use in SATA RAID, and I'm wondering whether I can have them as one big partition, or if I can do them separately.

**Paul M** · 10-07-2004, 00:03

It's considerably larger than any drive you can buy

Some older BIOS's do have a limit - just under 140GB - but if you have a modern M/B and BIOS then this should not be a problem either.

10-07-2004, 00:03

I wouldn't recommend having 2 HDD's as one partition, Iv'e heard it's not very safe. I would have them both as there own partitions to be on the safe side.

Tristan · 10-07-2004, 00:07

Quote:

Originally Posted by Pem

It's considerably larger than any drive you can buy

Well I've read that NTFS can have single paritions of up to 4TB. But then I've also read that XP itself won't recognise paritions of more than 137GB. So I was just wondering what the "official" answer was!

Electrolyte: having two drives working as one is the whole point of RAID (or RAID 0, anyway). It does mean that if you lose on drive, then all your data is lost, but that's what backups are for

**Paul M** · 10-07-2004, 00:11

Quote:

Originally Posted by Tristan

Well I've read that NTFS can have single paritions of up to 4TB. But then I've also read that XP itself won't recognise paritions of more than 137GB. So I was just wondering what the "official" answer was!

That limit is a bios limit - I added it to my reply above - but not quick enough

Windows XP (and W2K) will handle anything the bios can throw at it - I have GB+ partitions at work [on W2K machines].

**Paul M** · 10-07-2004, 00:15

Quote:

Originally Posted by Electrolyte

I wouldn't recommend having 2 HDD's as one partition, Iv'e heard it's not very safe. I would have them both as there own partitions to be on the safe side.

Tristan says he has a SATA RAID card to join them - this is perfectly safe and is what RAID cards are designed for.

Tristan · 10-07-2004, 00:32

Pem, you really seem to know what you're talking about, so maybe I can run my whole plan past you and the rest of the guys here

I currently have 80GB and 20GB ATA133 drives. I use Windows XP on the 80GB drive, and Linux on the 20GB one.

My plan went like this: to buy two SATA drives for use as a RAID array under Windows XP (my motherboard supports this). Then format my 80GB drive, and use that for Linux (and probably bin the 20GB one to make some room in my case). I'd probably allocate 10GB or so on the latter drive as a FAT32 partition, so swap data between Windows and Linux (Linux can't write to NTFS currently, and I don't know what the RAID drivers are like).

But it's just dawned on me that I could also put an image of my Windows installation CD, and possibly even the Suse DVD, onto that 10GB partion, and install from there. Far quicker and easier than using CDs. Is this possible, or am I dreaming? Could I boot using a Windows 98 floppy, change to the installation parition and then run setup from there? Does Linux have a programme that would start installation from MS-DOS, or do they *require* you to boot straight into Linux? And how would I go about setting up the paritions in the first place?

All answers gratefully received... and apologies if I haven't explained myself very well. It's late!

**Paul M** · 10-07-2004, 01:24

I cannot answer all your questions - the only thing I know about Linux is how to spell it.

There is certainly nothing to stop you creating a FAT32 partition, putting the Windows installation files on it and then running the install from there - it is common practice. If you boot up with a Win98 floppy then you can use Fdisk to create the partitions.

keithwalton · 10-07-2004, 01:34

The 137GB limit is not just a bios limit, xp pre sp1 also has the limit. So does 2000 to a point (sp3 i think fixes it could be 4). I've found recently that it is worthwhile to have you os installed a relatively small partition (mines 5GB) and have only critical programs installed to that partition and everything elsewhere. I've found it helps keep windows speedy and defrags on the windows partition quick and easy.

K

Richard M · 10-07-2004, 01:50

Quote:

Originally Posted by keithwalton

The 137GB limit is not just a bios limit, xp pre sp1 also has the limit.

That cannot be right because I've used a 250GB partition before now with XP Pro.
AFAIK, XP only hits the limit at around 48TB, but I could be wrong

BTW - Don't use FAT32, it's very outdated - NTFS is a lot more secure and efficient.

**Paul M** · 10-07-2004, 01:51

The following applies to Windows NT, but these limits have, AFAIK, been carried forward into W2K and XP and most likely increased.

Quote:

File Systems
FAT and HPFS both have internal limits of 4 GB due to the fact that they use 32-bit fields to store file sizes. NTFS uses 64-bit fields for all sizes, permitting its data structures to handle volumes up to 2^64 bytes (16 exabytes or 18,446,744,073,709,551,616 bytes).

This value is the theoretical limit for the NTFS file system. Practical limits having to do with the maximum allowable partition size described above limit the size of an NTFS partition to approximately 2 terabytes. Because the 32-bit fields of the partition table refer to the number of sectors in the partition, disks with larger sector sizes translate into larger permissible partition sizes. Currently Windows NT supports sector sizes up to 4 Kilobytes. With 4KB sectors, Windows NT can support a 16 terabyte partition. As new hardware or software schemes become available, NTFS will be able to handle substantially larger volume sizes.

Drive and Controller Types
IDE drives use a different data structure for representing the number of cylinders, heads, and sectors per track than the partition table and BIOS INT 13 interface. According to the IDE specifications, the maximum number of cylinders is 65536, the maximum number of heads is 16, and the maximum number of sectors per track is 255. This yields a maximum of 136.9 gigabytes, but because the BIOS/IDE interface has been constrained to use the lowest common denominator, the result is a limit of about 528MB for an IDE drive on an Intel-based ISA bus computer. There are new drives and drivers which use an "Enhanced Drive Parameter Table" to translate between the logical sector layout internal to the IDE drive and the logical sector layout addressable by the BIOS INT 13 interface. These drivers and devices can support larger disks. The SCSI II command set uses its own form of sector addressing which currently supports disks as large as approximately 7 gigabytes.

Xaccers · 10-07-2004, 03:37

Quote:

Originally Posted by Tristan

Pem, you really seem to know what you're talking about, so maybe I can run my whole plan past you and the rest of the guys here

I currently have 80GB and 20GB ATA133 drives. I use Windows XP on the 80GB drive, and Linux on the 20GB one.

My plan went like this: to buy two SATA drives for use as a RAID array under Windows XP (my motherboard supports this). Then format my 80GB drive, and use that for Linux (and probably bin the 20GB one to make some room in my case). I'd probably allocate 10GB or so on the latter drive as a FAT32 partition, so swap data between Windows and Linux (Linux can't write to NTFS currently, and I don't know what the RAID drivers are like).

But it's just dawned on me that I could also put an image of my Windows installation CD, and possibly even the Suse DVD, onto that 10GB partion, and install from there. Far quicker and easier than using CDs. Is this possible, or am I dreaming? Could I boot using a Windows 98 floppy, change to the installation parition and then run setup from there? Does Linux have a programme that would start installation from MS-DOS, or do they *require* you to boot straight into Linux? And how would I go about setting up the paritions in the first place?

All answers gratefully received... and apologies if I haven't explained myself very well. It's late!

Ditch the 20GB, it's probably only ATA66 anyway.
Set up a hardware raid 0 with the SATA drives, creating a logical drive of the whole size.
(If you don't have SATA raid and you have to use dynamic disks in XP, then if memory serves, create a small (10GB) system partition and instal XP on it, then once XP is up and running, convert the free space into a dynamic disk and the other SATA disk and combine them)
Bung your XP CD in the drive and boot up (you may need a SATA raid driver, in which case this should be on a floppy that came with your motherboard).
If you need the extra drivers, put them in when prompted and follow the on screen instructions.
Once you've got XP installed on the logical drive, you can then install your 80GB, partition it as you want it, copy across the XP and Linux cd's and install linux
It should then detect XP as being installed and set up lilo properly so you can dual boot.
(its been a while since I played with linux though)

10-07-2004, 10:32

Quote:

Originally Posted by Pem

Tristan says he has a SATA RAID card to join them - this is perfectly safe and is what RAID cards are designed for.

You learn something everyday

KingPhoenix · 10-07-2004, 10:42

Quote:

Originally Posted by keithwalton

The 137GB limit is not just a bios limit, xp pre sp1 also has the limit. So does 2000 to a point (sp3 i think fixes it could be 4). I've found recently that it is worthwhile to have you os installed a relatively small partition (mines 5GB) and have only critical programs installed to that partition and everything elsewhere. I've found it helps keep windows speedy and defrags on the windows partition quick and easy.

K

This is true, i had a nightmare of a mission to install my 250Gb hard drives because my windows xp disk was pre sp1... i had to partition it so that it could see the drive in the windows installer, install windows then use partition magic to get the rest of my drive available. But i now have a OEM sp1 disc, and no longer have this issue... (running 2 x 200Gb SATA drives and 1 x 250Gb ATA drive no problems all running at full size)

tkiely · 10-07-2004, 10:49

You should also keep large boot partitions regularly defragged. Is is possible for fragmentation to move the files required to boot out of the part of the partition that can be read by the BIOS.