My computer contains two hard drive, 3TB and 8TB and the motherboard is P67A-UD3-B3. When I tried to install Windows 7 on each of them separately, it was automatically converted to MBR and their sizes were limited to 2TB. Can it be fixed, meaning installing Windows 7 on each of them without loosing size, or should I consider buying a 2TB hard drive in order to avoid loosing size?
Why would you want Windows on 2 different disks? What are you trying to do, ideally?
Which of those 2 disks would you PREFER to put Windows on?
Booting from a drive greater than 2.2 TB requires GPT partitioning and UEFI, not BIOS. A system with BIOS cannot boot a GPT disk.
Does your motherboard provide BIOS or UEFI? That's an older P67 chipset so may be BIOS only.
Can you initialize the 8 TB disk as GPT and use it purely as a data disk, with no operating system? Maybe not on a drive that large with a motherboard that old.
Some motherboard manufacturers supply a downloadable bit of software that can work around the issue.
How much space do you need for C? I'd be tempted to buy a smallish SSD of maybe 128 GB and put Windows on it, using MBR.
At the beginning the operating system was installed on the 3TB, while the 8TB was the backup drive. However, the drive was recognized as 2TB only, so I tried to figure out it it's possible to define it correctly as 3TB. How can I tell if the motherboard supports UEFI? Google shows some results when typing "P67A-UD3-B3 UEFI", but I'm not sure. The ideal situation is that both of the drives contain their full sizes, if it's possible, since most the SSD sizes are too small for me, and the big ones (1TB+) are quite expensive. Should I pass on that 1TB, and leave it as 2TB instead of 3TB? Is it an issue of Windows 7 only, or will it be the same with other operating systems (Windows 8 / Windows 10) as well?
Here's your motherboard at Gigabyte site:
GIGABYTE - Motherboard - Socket 1155 - GA-P67A-UD3-B3 (rev. 1.x)
which says:
"Hybrid EFI Technology combines the benefits of GIGABYTE's mature BIOS platform including stability and compatibility with 3rd party products with 3TB+ HDD support from EFI technology, allowing GIGABYTE to offer the best of both worlds through a quick and easy BIOS update using GIGABYTE's @BIOS utility that is freely available from the GIGABYTE website."
It's from 2011. Trying to decipher the marketing gobbledegook, my guess is that it has a BIOS and does not offer UEFI.
Which would mean you can't initialize it as GPT and use it as a boot drive. But I'd think you could use MBR, let it be restricted to 2.2 GB, and use it as a boot drive.
The "3 TB+" support thing is what I referred to in my first post--intended to allow you to see all the drive without going to GPT.
I have NO repeat NO idea if it works well or is a mess that should be avoided.
If you want to try it, you would go to the "utilities" download area from the above link and download and install the "3 TB Unlock" gizmo.
You may or may not have to also update your BIOS. I dunno.
I don't know if that 3 TB thing would be useful to you for your non-Windows drive. However: your motherboard may or may not support 8 TB drives of any type. You may ultimately be limited by that and be able to see only portions of the 8 or maybe nothing for all I know, even with the 3 TB unlock tool.
I don't know how much data storage you need and I don't know why you bought an 8 TB drive.
Windows needs only 20 GB. Why specifically would a 128 GB, 256 GB, or 500 GB SSD be "too small"?
Millions of people use SSDs of 128 GB and under. If you in fact have 1 TB of data as opposed to applications, then obviously it won't fit on a 500 GB SSD, but that's an unusual situation.
My inclination would be to do one of the following:
1: Buy a relatively small SSD and put Windows and applications on it, using MBR or GPT, whichever you want. Use the other drives for data only.
2: Put Windows on the 3 TB drive using MBR and concede the .8 TB it won't allow you to use--rather than get involved with that 3 TB unlock thing. You'd have to decide if that extra .8 TB is worth fiddling with that tool.
You probably paid a pile of dollars for that 8 TB drive, so you need to find out if you can use all 8 TB of it, with the unlock tool, GPT, or whatever else you can come up with. If you can't and it's limited to 2.2 TB, that's a big waste of money on unusable capacity. Is it returnable?
Put the Windows 7 drive in the OD and reboot the PC while tapping the one-time BIOS Boot menu key. Does it offer a UEFI or EFI DVD drive choice? If so boot it into the WIn7 installation media to delete all partitions, create and format new and it wlll convert to GPT and set Windows Boot Manager first to boot.
If no EFI choice on boot menu with DVD in drive, reboot into BIOS setup and look for UEFI, EFI, CSM, Legacy BIOS, or Secure Boot settings on all tabs.
If no UEFI, format a 1gb install partition for Win7, then after install in Disk Mgmt create other data partitions on the drive as desired.
That web page also says:
so it must have GPT support.GIGABYTE DualBIOS™ now supports 3TB+ (terabyte) hard drive booting without the need for partitioning, and enables more data storage on a single hard drive.
May have to update the BIOS first from what this says:
The board manual also says:best of both worlds through a quick and easy BIOS update using GIGABYTE's @BIOS utility that is freely available from the GIGABYTE website."
CD/DVD Boot Option
Set this item to EFI if you want to install the operating system to a hard drive larger than 2.2 TB. Make
sure the operating system to be installed supports booting from a GPT partition, such as Windows 7 64-
bit and Windows Server 2003 64-bit. Auto lets the BIOS automatically configure this setting depending
on the hard drive you install. (Default: Auto)
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