What?! A “Windows only” hard disk??

Came across these Western Digital Black2 Dual Drive units the other day. What a cool idea I thought! Just the thing for a couple of laptop users here at work who prefer the speed of an SSD in their laptops but would like a bit of extra room for VM’s and the like.

So I ordered three – one for my work iMac as well. I’d recently upgraded the iMac with an older 256GB SSD – which was fine – though not a huge amount of space obviously.

The units arrived and I set about hooking it up to the iMac using the handy USB->laptop drive SATA cable that it came with.

Only the 120GB SSD drive portion appeared.

Digging a little further, I found that the unit is supported in Windows only – you need to install software in Windows to enable access to the 1TB disk in the Black2 Dual.


Once I’d finished ranting about how crap it was that a hard disk vendor would build a hard disk only for Windows, I had a think. There *must* be a way to make this work – surely! Just because they haven’t built this ‘enabler’ software for OSX surely doesn’t mean that it absolutely wouldn’t work.

So, I went to work getting it set up on a Windows laptop, figuring that I could unlock the disk in Windows & then pop it back in my iMac and configure a Fusion drive across the two disks.

Annoyingly – or cleverly I guess, depending on how you look at it – you cannot unlock the 1TB portion of the drive while it is connected via USB. It actually has to be resident inside the machine (or at least, connected to the SATA bus) to unlock.

This meant I had to image the existing SSD in the laptop onto this one – using the afore mentioned handy cable.

Once it was unlocked, I connected it up to the iMac and converted the partition table from MBR to GPT using the gdisk utility. Note that the 1TB portion shows up as a partition NOT a second hard disk I had suspected it might based on the reviews I’d read.

I removed all the partitions from the first 128GB of the disk and created an EFI partition then ran the Apple Recovery Disk Assistant tool to create a Recovery partition on the new disk.

Excitedly, I then used the directions here to create the Fusion drive.

diskutil cs create Fusion disk3s2 disk3s3

Unfortunately this resulted in a POSIX Input/Output error so it seemed like that was the end of the road.
Frustrated, I posted a brief report into a MacRumours forum in which I’d left a question.

Overnight, “Weaselboy” replied with a few further links to check which renewed my hope that it might work.

One in particular – this excellent (as usual) article from Anandtech described how the controller uses LBA to address the different areas of the disk. Here was the reason for my renewed hope.

Ok, I thought, let’s just wipe the whole thing in my iMac and create the partitions again.

So I did.

And, this time, it worked.  Similar steps would mean this disk could be ‘enabled’ for use in a linux machine as well – it would work really well with / mounted to the SSD and /home on the 1TB mechanical portion.

19 Replies to “What?! A “Windows only” hard disk??”

  1. after you found out that it used lba. how has the drive been working for you? i currently have a 240gb ssd and a 500gb hdd in my MBP early 2011 and i was looking at a black2 to replace my 500 gb hdd and use the ssd part for windows boot drive and the 1tb drive for a shared data drive between osx and windows 7.

  2. Thanks for the question. Yes, it's still going fine as the main Fusion drive in my work iMac. Nice and fast, plenty of storage.

    The two we also have in a couple of HP laptops here (running Windows 7) haven't reported any issues – apart from a drop in battery life due to the mechanical disk component.

  3. Are there any how to links for the last part. I'm sure I can connect it via SATA to a PC laptop, activate the 1tb portion. Then load it into my Mac. Once this happens.

    Do I just wipe all data and partitions installed? Then create the EFI partition as you did before and create a recovery disk partition and use that to install OS X? My only gap is how to create an EFI partition. That's new lingo to me.

  4. I am in a similar boat as Anthony. I have the drive unlocked and recognized by OS X. Did you simply repartition the drive in disk utility as a GUID EFI Partition? After that are you splitting the partitions as two “drives” (a 120gb and 1tb) and then running the terminal script to make the fusion piece work? This i the only part that I am stuck on. Thanks for any help you can give me.

  5. Hey there guys – thanks for the questions.

    I've just re-read through the post and I think the key is the last part “…just wipe the whole thing in my iMac and create the partitions again.”

    From memory, I didn't use any special command line options to do the partition creation – just Disk Utility.

    Here's a screenshot of my partition tables from 'diskutil list': http://twitter.com/donkey/status/465001929907519489/photo/1

  6. I got it working! I sometimes need to have more faith in Apple in simplifying things. I'm a power user and sometimes forget it is not always power that is needed to make things work correctly. I did have to create and separate the fusion drive a couple times before it was working stable. It is a slick little drive and I am very happy with the performance so far. Thanks for the help Donkey!

  7. That's great! Yes, very happy with the unit in my work Mac too.

    I have another on my desk to install in the other iMac at work (once it's passed warranty in a couple of months).

  8. I took my Macbook to a PC repair shop and got the 1tb portion activated in my WD black2 dual drive. I currently have windows 7 installed on it when I received my laptop back (picked it up to try and finish the last step myself since I need to use the laptop for my class and would rather get the OS X set up).

    My issue now is that the 120gb and 1gb drive show up in I windows my computer. But if I load up the macbook and hold Options to bring up disc utility and drive to wipe it and repartition the two drives through that. The only drive that shows up once disc utility loads is the wifi network selector and a single Windows drive. If I click on it, it just auto loads windows 7. I'm google the next step now. Seems donkey and Jon you both are a bit more educated in this Linux/hard drive partition basics. I'll keep googling a bit more and check youtube for assistance on what to do.

  9. Thank you so much for the instructions! Worked like a charm when preparing the new internal hard drive on USB. The key here is: wipe the drive in DiskUtil. Erase the whole drive, not just the single partitions, and recreate new partitions (of the same size).

    After that, everything is fine, and the drive is addressable and can be Fused.

  10. Is the disk slowed down by the fact that the SSD and HDD portions of the drive are both going through the same SATA 3, 6Gbit/s connection? Would it be any significantly faster to have separate solid state and hard disk drives so each has a dedicated SATA 3 connection? I am planning on upgrading the storage on my MBP. I could replace the optical drive with a second storage drive, but I'd like to just use the WD Black2 if the aforementioned isn't an issue.

  11. Hey there Anon! I'm not certain to be honest – I'm not getting particularly fast performance on my ~2009 27″ iMac but I think that's more to do with the SATA controller than the WD Black.

    Having said that, I'm still getting around 120MB/s read and 251MB/s write which is comfortably faster than the old 1TB Seagate spindle.

    I'd suspect you'll get a very nice speed bump with this unit in your MBP without needing to sacrifice the Optical drive.

  12. Awesome, thank you for your reply! I just want to make sure I can unlock the HDD portion if I get one. Is the following process correct?
    1) Replace internal hard drive of my old Windows laptop with the WD Black2
    2) Connect the old drive with a SATA to USB cable
    3) Change the boot order to load up Windows from the old drive
    4) Download and run program from Western Digital to unlock the other portion of the drive

    5) Replace internal hard drive of my MacBook Pro with the now unlocked WD Black2
    6) Connect the old Mac drive with a SATA to USB cable
    7) Boot to the recovery partition on the old drive
    8) Change something about the partition table (here is where I need help)
    9) Install OS X from the recovery partition on to the 120GB SSD
    10) Disconnect old Mac drive. Reboot (now within seconds). Profit

    If I missed anything, please correct me. As I said, step 8 is were I would like some help. I am comfortable in Disk Utility, but not with gdisk. I use Terminal often, but have no experience with gdisk. Could you please tell me what I need to do, and if it is possible in Disk Utility? Also, will each portion show up as an individual drive? I am looking for something such as seeing Macintosh SSD and Macintosh HDD, instead of just Macintosh HD. Thank you so much for your help, I am looking forward to this upgrade for my early 2011 MBP!

  13. Got it working as well as Fusion drive! Well written blog!

    Though, do you use Trim Enabler for the SSD Part or doesn't it matter, because of the Fusion setup?

  14. Thanks for all your kind feedback and questions.

    I haven't used the Trim Enabler at all – last time I fired it up, it didn't have any support for the Black2.

    I'm also in the process of installing a second one here at work – I'm writing up the process in a nice bullet point form from whoah to go.

    I'll pop it in as a new blog post and link it here in the comments once it's done. 🙂

  15. What are the LBAs roughly for the drive? I'm sure there are tools that can make partitions from specific LBAs.

    My best worst idea yet was to get 4 of these things and try to put them into raid 1+0/0+1 and make the partitions such that there's an SSD partition, some empty space to act as a spacer if I can't get the exact LBAs, and then the HDD partition.

  16. Hey there Matthew – I'm not sure to be honest. I'm happy to run a command or something if that would give you the information you need.

    Perhaps the Anandtech article linked in the post will be able to provide the answers you seek.

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