OWC Thunderbay 4 mini Thunderbolt 2 Enclosure Review – 2TB SSD Storage at 1340 MB/s


The test Bench we are using for Intel ThunderBolt 2 tests is that of our Z87 Test Bench which contains the ASRock Extreme 11/ac with two ThunderBolt 2 ports.  We also have a Z97 test Bench, with the updated ASRock Z97 Extreme 11 that also incorporates ThunderBolt 2, however I haven’t this on hand as it is a few thousand miles away with one of our reviewers.  We wanted to mention this Z97 Test Bench, not only because it was used in testing the OWC ThunderBay 4 RAID 5 device, but also, we found a peculiarity when using ATTO between both systems that we will get to.



This Test Bench build was the result of some great relationships and purchase; our appreciation goes to the below mentioned manufacturers for their support in our project.  Our choice of components is very narrow, in that, we choose only what we believe to be among the best available and links are provided to each that will assist in hardware pricing and availability, should the reader be interested in purchase.

PC CHASSIS: Cooler Master HAF Stacker 935 EATXblank
MOTHERBOARD: ASRock Z87 Extreme11/ac EATX MotherBoardblank
CPU: Intel Core i7-4770K Haswell 3.5GHz Quad Coreblank
CPU COOLER: Cooler Master Seidon 120Mblank
POWER SUPPLY: Cooler Master V1000blank
SYSTEM COOLING: Cooler Master 120mm Red and Green Fansblank
GRAPHICS CARD: EVGA GTX 770 Superclocked with ACX Coolerblankblank
MEMORY: Crucial Ballistix Tactical Tracer Memoryblank
KEYBOARD: CM Storm QuickFire XT – Limited Editionblank
MOUSE: CM Storm Sentinel Advance 2blank
MOUSE PAD: blankCM Storm Control-RX Large Gaming Mouse Padblank
6x MOBILE RACK Icy Dock ToughArmor 6x SATA/SAS HDD/SSDblank
4x MOBILE RACK Icy Dock ToughArmor 4x SATA/SAS HDD/SSDblank
DISPLAY MONITOR QNIX QX2710 27? 2560×1440 Display Monitorblank
DUAL MONITOR MOUNT Rosewill Dual 27? Monitor Mountblank
MONITOR WALL MOUNT Rosewill RMS-MA3210 Wall Mountblank


ATTO Disk Benchmark is perhaps one of the oldest benchmarks going and is definitely the main staple for manufacturer performance specifications. ATTO uses RAW or compressible data and, for our benchmarks, we use a set length of 256MB and test both the read and write performance of various transfer sizes ranging from 0.5 to 8192kb. Manufacturers prefer this method of testing as it deals with raw (compressible) data rather than random (includes incompressible data) which, although more realistic, results in lower performance results.

OWC TBay 4 Mini ATTO

We can see that there seems to be a steady high transfer speed just above 1GB/s which is obviously well above what we saw in ThunderBolt, however, it seems just a bit odd that the final read transfer speed of 1.3GB.s was accompanied by a write transfer speed that seemed to drop a bit to 930MB/s.  We thought we had seen something similar before, and then remembered testing the OWC ThunderBay 4 RAID 5 device on our Z97 test Bench.  Check the ATTO result out in this link.

Up next is our Crystal Disk Mark result which is definitely lower, however, special attention should be paid to the low 4K write performance, remembering of course that this is an external device and these lower results are typical.

OWC ThunderBay 4 Mini Win7 TBolt 2 CDM

Last but not least, we have one final look at QuickBench 4.0 that displays the slightly lower speeds of Intel ThunderBolt 2 results that appear pretty consistent, at least with both ASRock boards we have on hand.

OWC ThunderBay 4 Mini Win7 TBolt 2 QuickBench


  1. blank

    Why did you show not even a single picture of its interior? You call that a review? Stop kidding! Chips matter. You photograph SSD chipsets, so please reveal what is inside ThunderBay 4 Mini.

    (Need I remind you: ThunderBay 4 notmini contains four count ASM1061.)

  2. blank

    On the 4th sentence of the first paragraph (page1) it said “yet capable of speeds up to 1.4MB/s”, that doesnt sound right or did you mean 1.4GB/s ?

  3. blank

    I am trying to find out whether this unit honors write barriers, which are critical to data security ( see this thread: https://markmail.org/thread/shrs46f6lixkqllw ). Without them, a sudden power outage or an unexpectedly pulled cable can easily make a RAID completely unrecoverable by mere mortals. Have you tested that?

  4. blank

    Planning on upgrading from old MacPro running Crucial SSDs to Retina iMac. Will this TB Mini accept non-OWC drives in non-RAID config.

    What happens when the TB cable is not attached. Will the drives power up and idle?

Leave a Reply

Your email address will not be published. Required fields are marked *