X300 8tb drive works fine on a mac, assuming you don't encrypt anything on it
I am a mac user, so what i'm about to say probably does not apply to a pc. I just bought a new 2017 imac and it is loaded with the fastest 4.2 ghz i7 quad-core processor, a 3tb fusion drive, and 64gb of ram, running sierra. Speed should not be an issue. I bought a pair of these drives to store some files that i prefer to keep in encrypted .Dmg containers. Disk utility makes it easy to make such containers. When you do the math, you realize that even when writing at usb3 speeds, about 100 mb/sec, it will take about 24 hours to fill up an entire 8tb x300 drive with this encrypted container. After the first drive was written to, i found something that did not seem right: when you enter the password and open the container, all writes to it are dog slow, as in 5-10 mb/sec. That's not right.At first i attributed the problem to the drive, so i opened the second x300 drive and repeated the operation, but found the same slow write speed to the opened container. One drive bad, okay. Two drives bad? No. Using disk utility's first aid showed no signs of issues with the drive. Any other writes to the drive to non-encrypted folders, or a non-encrypted container, and the speeds are normal. Reads from either encrypted or non-encrypted folders/containers are as well normal-fast.Some internet research revealed that this problem has been going on for many years and several releases of osx. It would appear that the slow write speeds to an encrypted container are not a function of any hard drive, but a bug inside mac osx. The same internet research found neither a solution nor a workaround. I worked at it and found that there is a workaround, although it's not fast or easy to do. What you do is find yourself an old mac that runs snow leopard (10.6.8). I have an old imac that fits the bill, but unfortunately, if it runs snow leopard, it means that its ports are limited to either usb2 or firewire800 (fw800). Writing to these big-capacity drives when your speed is limited to 20-40 mb/sec is going to be slow. I was able to put the drives in a fw800 enclosure to get a faster speed than usb2.You now use disk utility in the snow leopard-based mac and make the encrypted container on the x300 drive using it. It took about 2.6 days to complete. When complete, you then move the drive over to your newer, fast mac and connect it up through usb3. When you open the encrypted container, make in snow leopard, mount it on the sierra-based mac desktop, you find that write speeds are finally what you expect, about 100 mb/sec. I think i'm the first guy to find a viable workaround for this issue. It verifies that the issue is a bug buried in later versions of osx, which according to some people goes back all the way to lion (10.7). It's an apple bug. The observed slow write speeds to the encrypted x300 drive is not a problem with the hard drive.Additionally, once you are running on the new fast mac, you can copy this encrypted container to any other drive (the second x300 drive that i bought), and when you open it, the write speeds are again fast as they should be. In other words, it is just the creation of the encrypted container that is the bug in apple's later disk utility code. Formatting, reading, and copying are just fine. How you manage to slap apple's face to get them to fix it, i don't know.Sorry for the long story, but the slow write speeds to the encrypted container would have been a deal breaker for me. I would have wrapped up the drives and sent them back, blaming the hard drive for what turned out to be a mac osx bug. I have found that these drives perform as well as you would expect them to with no slowness or other oddness that i first attributed to the possibility that these drives might use smr (shingled magnetic recording) that is notorious for slow writing speeds. Toshiba won't tell anyone what technology is inside their drives, but industry insiders swear it is not smr. Reads and writes now operate reasonably fast on usb3 for my needs, regardless of whether there is encryption involved or not. You just have to be careful not to use any osx version of 10.7 or higher to make an encrypted container.