4TB external, 2.2TB limit

ch33r

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Yes, we all remember the 127GB HD limit at the dawn of the new millenium. Now we have reached another hurdle, the 2.2TB limit that wont just be simply fixed with a windows update. So now I need to know what the rules and limits are of having a hard drive bigger than 2.2TB, such as a Seagate Barracuda XT 4TB HDD. I am looking to buy a black lacie 1TB external hd... You know... the one with the blue light underneath at the front. When it arrives at my door, I plan to take out the 1TB HDD out of its black enclosure, and put a 4TB in its place... But I need to know. How will my PC and others react when I plug it in via usb cable. I want the OS to see one full volume as 4TB.

My questions go as follows:
Will it work with Windows XP 32-bit or 64-bit?
Will it work with Windows Vista 32-bit or 64-bit?
Will it work with Windows 7 32-bit or 64-bit?
MUST it be formatted with GPT, or can it work at all on MBR?

I've read that if you plan to use it as your windows install drive, you can't use MBR. Or can you with EFI bios? I dont plan to use it for a windows install, just external storage. Can I get away with MBR or must I use GPT? How will BIOS's that are not EFI react when the drive is plugged in? How will the different versions and bit's of windows react when its plugged in. Can you boot from it if its GPT or MBR on a non-EFI bios? Or is it not possible at all to boot it on a PC with a non-EFI bios? Can an EFI bios install windows on it with MBR instead of GPT???

I know these are a great many questions.... But I need to learn all about the 2.2TB limit so I dont screw it up... Can someone answer my questions??? Please???
 

ch33r

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So theres absolutely unequivically no way to get higher than 2.2TB on one volume on MBR, no matter the OS or no matter the type of BIOS, any BIOS or any OS it MUST be GPT to have 1 volume as 4TB??????
 
Seagate's 3TB GoFlex drives and WD's 3TB My Books are compatible with Windows XP right out of the box. The both use single 3TB MBR partitions.

In fact the limit on MBR partition size is not a capacity limit per se. Instead the partition size is limited by the largest number that can be represented in 32 bits.

That is, the maximum number of sectors in a partition is 2^32. This means that the maximum partition size for a drive that has a sector size of 512 bytes is ...

2^32 x 512 = 2TiB

http://www.google.com/search?q=2%5E32+x+512+bytes+in+terabytes

The way that WD and Seagate circumvent this limitation is by configuring their 3TB externals with an LBA size of 4096 bytes. This results in an MBR limit of 16TiB.

Some other high capacity enclosures are configured with 512-byte LBAs, but they enumerate themselves as two physical drives, each with a capacity less than 2TiB.
 
Windows XP cannot natively recognise GPT partitions, but Paragon has a GPT driver for Windows XP. Hitachi also has an OEM version of this driver which is available for download by their customers.

http://www.paragon-software.com/technologies/components/gpt-loader/
http://www.paragon-software.com/docs/GPT_Loader_CaseStudy.pdf

As for your other question ...
http://en.wikipedia.org/wiki/GUID_Partition_Table

"MBR-based partition table schemes insert the partitioning information for (usually) four 'primary' partitions in the master boot record (MBR) (which on a BIOS system is also the container for code that begins the process of booting the system). In a GPT, the first sector of the disk is reserved for a 'protective MBR' such that booting a BIOS-based computer from a GPT disk is supported, but the boot loader and O/S must both be GPT aware. Regardless of the sector size, the GPT header begins on the second logical block of the device."

 

Newb888

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I'm in the same boat and I am a too a bit unclear as well with the responses.

This is what I DO know so far. On non UEFI mobos we can't install any windows on a HD larger than 2 TB.

The question remains is whether or not these external HDs that are over 2TB in size will work with Windows, and if so, with what versions? I am looking for a HD, either external or stand alone that I insert into HD dock.

Amazon has some deals every now and then on 3+ TB HD enclosures that are actually cheaper than the same 2 TB HDs. So clearly, those of us who bought a new system just prior to the implementation of the UEFI protocol got scr ewd big time.