WD Blue 3TB Shows up in Windows 7 x64 as 748GB

I got a 3TB Blue to replace an old Seagate 500GB drive.
Windows 7 x64 system, AMD chipset.

Acronis WD Edition cloned the old drive to the new one, but, it only shows up as 748GB in Windows.

Note, when I did the cloning using a USB enclosure it allowed me to do the full 3TB.
When it didn’t boot, I connected it internally, and re-did the cloning, noticing that it only allowed 748GB to be allocated on the new drive.

My mobo/OS apparently doesn’t support GPT, so it has to stay MBR.

After successful cloning and booting with the drive internal, I decided to try and fix it with GParted.
Booted into GParted, and expanded the partition to 1.9TB, and it won’t boot.
Changing it back to 748GB and I can boot again.

Tried a lot in GParted, it was able to give me 1.9TB plus 1TB partitions even though it’s MBR, but anything beyond 748GB allocated means Windows won’t boot.
Just to clarify this point, in Linux, the full 3TB drive is visible and able to be formatted.

In Windows, it shows up as 748GB, completely allocated.
If I allocate more than 748GB outside of Windows, it won’t boot.
Any size less than 748GB allows boot.

BIOS appears to be fine, just to re-iterate. BIOS shows

I see lots of posts like this, and people fix it with Intel RST drivers, but my system is AMD.

This feels like a driver issue of some kind, but I don’t see any evidence of there being drivers for me to check.

Any thoughts?

Hi Fendletruck,

It is recommend to check the health of your WD Blue drive using Data Lifeguard Diagnostic tool. If passes, then reformat it in GPT partition table from other computer if your computer not support GPT. After this you can make a clone copy with un-allocated extra storage apart from the cloned volume.

When you say 748GB, do you mean that Windows can only use the first 748GB of the drive, or that there is 748GB unusable space after a 2TB usable area?

If the former, it could be any combination of BIOS or Windows, or even Microsoft’s copy protection kicking in. That Linux can use the whole drive suggests it isn’t hardware.

In the latter case it is an MBR limitation. Only a UEFI BIOS can boot from GPT. Windows 7 64 bit can use GPT, but 32 bit can’t. If Windows and/or your BIOS can’t do GPT, there isn’t anything you can do for the Windows side of things besides upgrading them.

The simplest solution is to reconnect your old drive as a boot/Windows drive and format the new drive with GPT as your Linux drive. You will still need /boot on the old drive, but the rest can move to the new drive. If you are comfortable with Linux this is easy to set up.

While it is possible to set up a hybrid MBR/GPT partition to give Linux the last 748G, this is an advanced setup that will need an experienced Linux admin to create. I don’t recommend it. Replacing your motherboard/upgrading Windows is preferable.

When I say 748GB, I mean, the drive shows up as 748GB only.

Not left-over, not per partition, but the entire disk says it has a capacity of 748GB.
I can make partitions on that 748GB disk, up to, and including 748GB in size.

My Windows 7 edition is 64-bit, but my BIOS isn’t UEFI, it’s legacy.

I’m aware of the MBR limitation, and I’m fine only being able to use 2TB of the 3TB drive, but only being able to use 748GB is very annoying.

I don’t want to boot Linux. I only did so from a live CD because I wanted to expand the partition, because I see that some people resolve their issues using this method.

I’d love to figure out what’s going on with BIOS/Windows/Copy Protection/etc… but the only info I can get from WD is “check your drive health with Data Lifeguard Diagnostics”. The drive is fine…

Yeah, that sounds like a BIOS problem, probably an overflow error. If you can’t upgrade the BIOS, your next option would be to replace the motherboard. Sorry, bad luck. :frowning:

Doesn’t Linux use the same BIOS?

Linux only uses the BIOS during the bootloader. It uses its own drivers after that which don’t even look at BIOS settings precisely because this kind of compatibility problem happened every time MBR was extended during the '90s. As long as /boot is in the readable area it doesn’t care.

I notice that on my system that the “boot” partition is a tiny 100MB partition, not the larger 740-odd GB partition.

Also worth noting, the old drive I was cloning from was 512GB, so I do have more allocated space on the new drive, so it’s not like I’m locked to the cloned size.

I’m going to see if there is any update for my BIOS, SATA storage controller, and try out the “ASUS Disk Unlocker”. I am thinking that my Asus update utility simply doesn’t work because this system is over 5 years old. Fingers crossed that something exists…

/boot isn’t supposed to be very big.

Which reminds me, is Windows on one big happy partition, or split between OS and data? Like /boot, the Windows boot/OS drive needs to be entirely visible to the BIOS.

Hopefully I understood the question enough, but the drive itself is 3 partitions currently:

  1. 100MB boot partition
  2. 40GB Recovery partition
  3. 708-ish GB Windows Installation

I temporarily had a 1TB partition in an effort to allocate more of my drive, but Windows wouldn’t boot, so for, now, that’s all there is.

This is in a fairly small case, that only houses a single HDD.

Yeah, it figures. Looks like updating your BIOS or your motherboard is your only option. Cheers.

Thank you. I very much appreciate your advice!

In all, getting 1TB out of a 3TB drive only cost me about $15 extra… Not going to lose sleep over it.

I would have screamed if you had told me to wipe the drive and run Data Lifeguard Diagnostics…

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