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Matt HodgeFlag for United States of America

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Problem with hard drive partition for a Win 7 PC

Hi - I have a newer pc that I'm replacing the hard drive to a 3 TB drive. When I boot up to the Win 7 64 bit DVD, i get to the place where the hard drive options are, and it shows 2 partitions on the 3 TB drive (see attached). The drive is split into a 2gb partition, and a 750gb partition. I'd like to have the HD as one 3TB hard drive with no partitions, and its not allowing me, it wont let me delete either partition. Is this a limitation, or is there something I'm missing? Any help would be appreciated.
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Seth Simmons
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is your bios configured to boot uefi?
if it isn't booting that way, you will have mbr which will have 2tb maximum
you can use diskpart at that portion of setup to modify the partition layout manually - including converting to gpt
you cannot have a bootable drive on W7 32 bit with a size over 2 TB
there is a bios /UEFI limit, and a OS limit
more info :

and for deleting the partitions, you can use the UBCD, there are tools on it for partition work
 i suggest to run some diags first - to be sure about the basics
Download the UBCD, make the cd, and boot from it
Here 2 links, one to the general site, and a direct link to the download
since the downloaded file is an ISO file, you need to use an ISO burning tool
if you don't have that software, install cdburnerXP :                              ultimate boot cd                        direct link UBCD

1. DVD Boot

When you boot via the DVD you MUST use the EFI boot and not the MBR boot which is the default ... so you have to use the keyboard combination to change the boot drive and you will see the EFI boot for the CDROM.

2. Hard Drive Preparation

The Hard drive must be cleaned of any partitions and (shift f10 at the drive prompt.. this brings up a command prompt... type 'diskpart' in diskpart
"list disk" -- this will show you a list of the drives connected (in case you have more than 1 hard drive)
"select drive X" where X represents your 3TB hard drive -- be careful as the next step is destructive
type "clean"
now type exit 2x and you are returned to the select disk in the Windows Installer, refresh then you can now select your 3tb drive.

3. Install Windows

and Install Windows 7
So, as said above - simply enable the uEFI boot in BIOS and then run install but on partition selection screen go to Advanced Options and delete all partitions from the drive. Since then it will automatically format your drive as GPT. Sure if there is uEFI boot support on your mobo.
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Hi - I did everything suggested above, and I believe the mb supports uEFI. I've attached 2 pics where i saw and enable uEFI in the BIOS. After doing this, I was able to boot with the Windows DVD and get into disk manager prior to installation of Win 7, and delete all partitions leaving it with the 2745gb drive. So, i installed windows everything looked good, until i went into "Computer" and it ONLY showed 2TB drive, I went again into disk manager, and saw there was a 745gb "unallocated drive". So, im not sure what i did wrong, if anything. If someone could look at the pics, and you'll see that uEFI is enabled. So like i mentioned, after doing above, i was able to delete the partitions, but after windows was installed, it still showed a 2 TB drive. Also, I see above that "ve3ofa" mentioned this:

"When you boot via the DVD you MUST use the EFI boot and not the MBR boot which is the default ... so you have to use the keyboard combination to change the boot drive and you will see the EFI boot for the CDROM. "

Im not sure what this key combo is for the "EFI boot", this is tghe only thing I didnt try.

Any help is appreciated!
Some people have reported problems with using the motherboards SATA controlled DVD-Rom and have had to use a USB connected DVD-Rom
You are using a single HDD on this machine and have RAID enabled, right? If yes then change the RAID mode to SATA mode.
Also make sure that the drive is completely empty (deleted all partitions). Then restart the machine again from the DVD and perform install to this empty drive.
@noxcho - yes, RAID is enabled,it seemed this was the only way that UEFI could be enabled, as displayed in one of the pics above. If I went back to SATA mode, no UEFI option
Ok, if you enable UEFI in RAID mode then switch to SATA and try to install it will install to MBR disk, right?
Yes, I'm not exactly sure how to tell if its installing to mbr disk, but I still get the same result, shows a 2tb partition, and a 745 gb partition - but only in windows! When I go into disk manager prior to installing windows, there only shows 1 - 2745 drive, with no partitions
Go to Windows prior to installing - means that drive is slaved to another machine, right?  Or are you referring to disk management of installation wizard?
Yes disk mgmt of installation wizard
and during the install - the 3 TB is the only drive connected?  then it should be ok
Yes - I'm just not sure why after windows is installed it only shows the 2tb drive accessible - if I go into windows disk mgr, I see the 745 gb drive there, but it's not enabled
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because you are still using a mbr type disk you need to be using a gpt type disk.  MBR disk only support up to  2.2TB
It turns out the MB wont accept any drives over 2TB
That is part of the MBR disk specification.. What exactly is your solution?
that's what i - and others have been telling you from the start