[8 to 90%] I bought this for my 2019 Mac Pro. It was simple to install. It comes with RAID software that doesn't quite work with Big Sur so I needed to download the beta version. OWC's customer service is wonderful. I'm really glad I got this.

[0.405 lb] I had a support chat with OWC first before ordering this because of the cost involved. Wanted to be sure that I was sure that it would work with my 2019 Mac Pro. They assured me it would, so I ordered confidently. Installation was simper than simple, just lift the top, place the card in a slot, replace the top, boom. Booted, holding my breath, and it showed up in the disk utility. But showed only 8.64GB of available storage. I tried the Erase (initialize) option, Still 8.64GB. Then, went into the partition setup of the disk utility, and voila, there it showed the full 4TB (well, 3.84TB) storage. Once I claimed it all for a single large partition and then reinitialized the drive (using MacOS Extended, Journaled), all was well. I was then able to make full use of the drive.

It seems funny to call it a drive, when it's actually just a thin chip on a PCIE-card. Even what you see in the picture there isn't really it. Most of that bulge is just heat sink. Amazing they can stuff that much storage onto something so small. Also a rather amazing amount to pay for a drive, but I wanted fast, non-internal storage, and lots of it, so felt the need and went for it. So far, it is behaving perfectly, is indeed fast. So after a few anxious 8GB moments, I'm relieved and happy.

[5 to 95%] mechanical drives are slow. I deal with large libraries and large files that are difficult to move around. This drive saves me so much time and makes my life so much more productive. You have to figure out a solid methodology first and follow a protocol. I do all my work off 2 SSD solutions and then at the end I move it to a mechanical drive (2 actually - one is main storage and the other is a mirror for those OHSHI moments). I use a script to move the items so life is carefree.

I did run the speed test software and you get what they say. Just wish that I could get more than 8TB as an option.

Somethings you regret buying. This isn't one of them.

[M.2 22110] Decked the OWC 8M2 out with 8 Samsung 980 Pro SSDs for best case testing. Never got close to the expected throughput. Only 10K sequential on Crystal Benchmark. Card worked with Gigabyte AMD X570 motherboard but would not boot with MSI Intel 670X. Clearly OWC has compatibility issues. During the first overnight burn-in test, the card completely failed. No longer warm to the touch so must be power issue. Since B&H dropped ship from a 3rd party, I'm forced to wait until the 3rd party issues their own RMA. It's now been over a week and no sign of the RMA despite emails, chat, and phone calls. I'm running back to Amazon.

[PCIe 4.0 x4] So far so good. Purchased a new base model Mac Pro 2019 and installed this in a 16x PCIe 3.0 slot in a striped raid for speed. I get an average of 5000MB/sec read and write. Slight issues installing which required a call to OWC tech support. They were very helpful and it was a known issue. So expect to do that. Otherwise working well!

[8 to 90%] This is a 5 Star item but you need to read my review as I learned a few things about installing and using this.


First, this is very, very easy to install in the older Mac Pro Towers and from what I have seen, even easier in the 2019 Mac Pro Tower. It literally plugs in and is good to go.


BUT, there is software that comes with this card and the activation key is on a sticker on the card so you need to write it down or, like me, you will be disassembling your Mac to take a shot of the code.


ALSO, this card DOES NOT support the APFS format which, in my case, is the format of my startup disk meaning that I was not able to use it as a startup.


SO, it goes so much faster than my current 2010 Hackintosh Mac Pro can take advantage of BUT when I get my new 2019 Mac Pro, I will be able to simply take this out of my current Mac and insert it and use it in the new one where it will save lots of time and $$$.


The SoftRAID software works very well once you use the provided activation code.


One last thing. This card heats up which was surprising to me as I have several SSDs and they hardly get warm. So, I am taking the precaution and turning my computer off when I won't be using it for more than a few hours instead of simply putting it to sleep.


One more last thing. I did get to work with OWC support and they were very easy to chat with, handled my problem quickly and I found out that there is no need to register the device as I believe your serial number or invoice will give them a date to use and the warranty is good for up to 5 years.


I am planning on using it for longer than that.