Make Windows see 3TB not 2TB

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I have a 3TB drive though Windows sees 1.99 of that. This is a MBR PC without GPT support. Since the BIOS isn't the new UEFI.
 
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SkyNetRising
There is software called Minitool Partition Wizard Free.
It supposedly is able to convert from MBR to GPT without wiping data.
But making backup is recommended anyway before such operations.
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On an MBR (Master Boot Record) disk, the locations where the partition sizes are stored are only 4 bytes long. Since this is in hexadecimal, the largest value we can stuff in there is all F’s. So the max value would 4,294,967,295 in decimal.

FF FF FF FFh = 4294967295d

This maximum partition size is not in bytes, it is in number of sectors. Since currently sectors are limited to 512 bytes, the maximum size ends up being 2 TB.

4,294,967,295 sectors * 512 bytes/sectors = 2,199,023,255,040 bytes or 2TB.

Source: https://blogs.technet.microsoft.com/askcore/2010/02/18/understanding-the-2-tb-limit-in-windows-storage/

What this means is you can either partition your drive as two partitions, 2TB and 1TB (or 1.5TB and 1.5TB, whatever adds up to 3TB).

GPT support isn't a BIOS issue, it's an OS issue. If you have Windows 7 or newer you have GPT support. The trouble is Windows can't boot from a GPT partition unless you have an EFI firmware, so you are indeed unable to boot Windows as-is from a 3TB partition.

You do have a few options beyond partitioning it into two drives, though it doesn't mean you'll ever have just one partition/drive letter until you upgrade your motherboard to one with UEFI. Personally I would suggest getting a 240GB SSD, putting Windows on that, and using the 3TB drive as a single 3TB GPT partition which you would give the name D:. Clearly this still leaves you with two partitions, but without UEFI you simply can't avoid that. Otherwise you can just use the two partitions. I took the SSD approach since I also lack UEFI, but the big RAID array I have does let me have a 4.77TB partition (according to disk properties, it's 5.25 trillion bytes which would be marketed as 5.25TB and reported as 5.25TB in Linux/OS X).
 
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On MBR disk this is not possible. Only first 2TB are accessible, rest is not.
For all 3TB of disk to be accessible it must be partitioned in GPT format.

 
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Ok so how do I make see the rest of that space. Considering that this is a boot drive. So what do I have to do make it see the "full" capacity and to make it a GPT drive? Thanks in advance
 
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If your motherboard doesn't support UEFI, then you can't use GPT partition format on boot drive.
You can use it only for secondary storage drive.

So - assuming you have already installed windows on MBR partitioned 3TB drive (2TB accessible):
1. Get another drive, clone windows and boot partitions to it, make it bootable;
2. backup everything from 3TB drive to somewhere else;
3. clean 3TB drive and change partition format to GPT (use diskpart or Disk Management for that);
4. restore data to your 3TB drive from backup.
 
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Will try as I've read this arcticle and can confirm that some of these don't work like the disk part or the AEOMI sill have to try gptgen which will be the death of me but then again Windows can't boot off of a GPT drive running in a non-UEFI motherboard/bios whatever... Or at least that's what I think.
 
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