ACASIS 40Gbps M.2 NVMe SSD Enclosure, TBU 405 for M1 M2 Pro/Max, Compatible with 、USB4/USB3.2/3.1/3.0/2.0, M.2 Enclosure Support 2280/2260/2242/2230 (TBU405)

Wow! What a few weeks it has been. For some, my initial review was blunt and critical. I had a unit arrive that initially worked, albeit slowly and not as expected. Soon after, the unit stopped responding and wouldn't mount a drive. I thought this product was garbage. However, I did some very thorough research. The product I received had been used before, and I unknowingly thought it was a new product. To summarize a very long story, the prior user did not insert the SSD in correctly, damaging the connector component and cracking (a few at least) solder joints that was making it work initially, but then as heat was applied the cracks became more apparent through thermal expansion, and BAM! The unit was dead. I initially thought this was a product malfunction, but this turns out to be on Amazon's side by returning used products and placing them as new. I had a lengthy conversation with the seller, and they are working with Amazon to ensure these things don't happen again. I agreed with them, that when you buy a new product, you should expect a new product, and not something that has been used before only for Amazon to throw it back on the shelf. This has apparently increased in frequency with Amazon, and thus this places blame squarely on them. Therefore, my review is below as I returned the defective unit, and bought a brand new one that I was able to test out. Like many of you, NVMe Enclosures are not a completely new idea, but they have remarkably increased in performance in the last year or two. This is because NVMe rely on the PCIe bus which typically is attached to a motherboard, offering the very best and top speeds that the motherboard is capable of handling. When you start moving toward enclosures, they are not "directly" attached to the motherboard, and thus are limited by the cable, receiver technology, and enclosure itself. Whereas USB (and Thunderbolt, for that matter) have promised to simplify this technology, it instead has increased its complexity to confuse all of us! First, you are looking for an enclosure. No surprise you already have a 2280 (think size, 22cm by 80cm SSD "stick", and NOT a SATA stick, don't bother with those anymore) SSD that you want to use, but either don't want to put it into a computer or you have a spare one on hand. That's where these enclosures come in handy; they can utilize the SSD attached to the computer as a "mega USB thumb stick" to increase storage and a whole benefit of other factors. Now, as we discuss speeds, USB sticks are actually surprisingly slow. Even some of the best, expensive ones are only able to pump out 100-200 MB/s write speeds (reading is almost always faster and easier than write). Since you are looking for an enclosure, you should have at least a 3,500 MB/s NVMe SSD that can benefit from a fast enclosure. Simply hook this up to a computer, and you'll get fast read/write speeds. This benefits from large file transfers such as videos, or a database of something like music (I myself have about 300 GB of personal music collection, not streamed). So the usefulness of a 1TB to 2TB SSD attached to the computer helps out your storage, while also performing well for the computer to carry out tasks that is within the extra storage space you are using. Enter ACASIS Thunderbolt enclosure. You'll see that it has the (not latest, but best) Intel JHL 7440 Chipset. You want this chipset because it is capable of Thunderbolt 3 (and Thunderbolt 4 for a Mac, a bit more about that difference in a second). This chipset gives you the capability to read and translate that data on the SSD to be sent to the computer. Next, you need the proper cable. Not just any cable with USB-C connections on each end. You need a cable that is capable of transferring that data from the enclosure to the computer. Any old "charging USB-C" cable won't do, they are for charging and NOT necessarily for data transfer. The cable that comes with this unit is meant for Thunderbolt 3/4, so this cable is good (and spendy). If you need a longer one, they don't make super long ones simply because the longer cable that you use, more interference is introduced and drastically reduces the speeds. Best to keep your cables short! Once you have the SSD, the enclosure, and the cable, you can now connect it to your computer or your laptop. The best benefits will be realized by a laptop as this enclosure is easy to carry around, does not weigh much, and performs WAY BETTER than any kind of mechanical drive that you plug into a laptop. This gives you the extra storage space you are looking for. Maybe for video editing, carrying around your music or photo collection, or even a backup that will be quick to backup any files that you need. This enclosure gives you that flexibility to use at your will, and giving performance similar to another SSD that is plugged into your motherboard. I installed both a 2TB WD SN850X and a 2TB Samsung 980 PRO (both are very good SSD's with fast read/write speeds) to test out the capability of these enclosures. I used a new Mac Mini M2 Pro and used a hard drive speed test software. Speeds were about the same between both SSD's, so the enclosure is pulling the best that it can from each SSD's. Even though these SSD's are capable of over 7,000 MB/s, the limiting factor is what Thunderbolt can do, and that is a theoretical rate of 40Gbps. But I'm going to clarify some negative reviews here with some technical know-how: First, remember that speeds are theoretical bandwidth speeds, and almost never reach those speeds. Think USB 2.0 and how everyone thought it was mega-fast at 480 Mbps, but it never got close to that. Know why? Because everyone kept trying to use mechanical drives, and they simply just can't perform like an SSD could back in the day, so speeds were still seemingly slow (still way better than USB 1.1!). Second, Thunderbolt (and USB 4.0) still have to have bandwidth reserved for display output. That means that the 40Gbps capable speeds still has about 16Gbps of reserved bandwidth for display carry-through. So yes, 40Gbps would yield over 5,000 MB/s, but you're not going to get that no matter what you do. So the best you can get is about 24Gbps, which is about 3,000 MB/s and that's exactly what this unit can do. I have not seen any other enclosure that can beat the performance of this one, simply as the best chipset right now is the JHL 7440 which will cap out data transfers at about 24Gbps (surprise!). Still, 3,000 MB/s is still VERY good, and you HAVE to remember that this is not directly connected to the motherboard, so you're not going to see 7,500 MB/s transfer speeds simply because you are not directly connected to the fastest bus on the computer. External connections are never really going to be faster than internal circuitry, so stop believing that somehow, magically, you can. Just isn't reality. So with that in mind, the enclosure can get warm with TONS of data transfers (how often are you going to transfer TB's of information back and forth? Yea, not much), so the heat dissipation is good. I found out that the hottest my unit could get was about 110 degrees F after moving 4TB of data back and forth, which is not bad at all. I also keep the heat down because it sits on top of the aluminum body of the Mac Mini, which helps pull heat out of the unit. The enclosure is a well machined block of aluminum alloy, so it is capable of heat transfer if you give it a medium to do that. Air is not exactly the best conductor, so sitting on top of a towel will not dissipate as much heat as you would if you placed it on a thick, solid metal surface, or even a cold, flat desk that can help pull some heat from the unit. To be fair though, it will only get hot with a LOT of work, and even then I noticed that it cools down fairly quickly, so heat is not really an issue with this unit. Lastly, I went beyond and wired up two of these units to give a real-world demonstration of a RAID setup (Google RAID if you need to learn about it, you'll want to if you haven't heard of it, RAID can be awesome). Using the same Mac Mini, I took two SSD's and two of these ACASIS enclosures, and set them up as a RAID 0 drive using Stripe. Now, I've taken two 2TB drives and created one single 4TB drive. As one transmits info, the other is getting ready to transmit, so they both work in harmony that essentially doubles your bandwidth. Behold, my 3,000 MB/s speed tests now turned into 6,000 MB/s speeds! That's the WOW factor that is needed. Overall, for about $100, this enclosure will beat the socks off of any of those "other" $20 or $40 enclosures. The JHL 7440 chip itself is expensive, not to mention the cable that is actually capable of full data transfer is not cheap either. Hence, the price is getting something worth paying for. You think USB 3.0 speeds are fast at 5Gbps? Try transferring a 30GB file and see the difference. Personally, I used a 30GB Photos library, which is a good test because it has hundreds of thousands of files, plus a large 30GB data chunk size, that is perfect to test a transfer rate. I moved 30GB in less than 30 seconds. Yes, half a minute. You read that right. How? Because I used my internal Mac Mini SSD with speeds of 3,500 MB/s and my RAID drive capable of 6,000 MB/s, and it transferred a large 30GB file that quickly. Just. Screamin'. Fast. So, to realize the full potential of this, you need to ensure that you have the right SSD, the right enclosure (this one), and the right cable (comes included). Now you are ready to play with power! Pic 1: Speeds of the enclosure using Samsung 980 PRO Pic 2: Detailed breakdown of Thunderbolt connection, 40 Gbps Pic 3: Box unit arrived it Pic 4: Internal Mac SSD, notice the speeds of ACASIS enclosure is near internal SSD speeds! Pic 5: Buy two of these, use RAID to combine the SSD's together for a whopping 6,000 MB/s!!!!

This enclosure is great for both PC and Mac. The installation was super easy and tool less function make it easy to change out the NVME. The speed was excellent when paired with a WD Black 850X NVME.

I've stress tested this some by moving a few large files to it one after the other. Thermal throttling was unnoticeable and the enclosure works as it should. If you need an external SSD for whatever reason, this is the route I would (and did) take. Pros: -40GBps -Thermally great Cons: -Cost Big on functionality, decent enough cost, but great form factor and easy to use.

Fast speed and solid construction. Sometimes it gets hot

It is connected to my Mac mini M2 for over a year now. This is the main drive. A 1tb nmve WD Black SN770. Tested also with a SN570 and read speed 2700, write speed 2200 Mb/sec. No heating problem in either summer or winter. Lots of dust over it. I clean with a artist brush once a whole. Still running without ever giving any trouble. Very reliable.

A lot of reviews here don't understand what this device is, or what you need to do to make it work right, without overpaying. So let me try to summarize. This enclosure uses the Intel JHL7440 chip, which is a PCIe 3.0x4 (Gen 3) chip. This is NOT a PCIe 4.0x4 (Gen 4) enclosure. That's fine, however, since the Thunderbolt bandwidth is also a limiting factor here. You will NOT be getting 40 gb/s, not even close, that is just slimy advertising, so read on. At best, you're going to get around 3000 mb/s read and write speeds, if you set everything up correctly. That, again, is due to the Gen 3 chip being used, and the bandwidth (speed) limitations of the Thunderbolt connection. That's just how it works. That also means that you don't need a top of the line Gen 4 NVMe drive capable of 7000 mb/s reads, because neither the chip nor the Thunderbolt connection can support that. In other words, a "fast" Gen 3 NVMe drive is likely to have the same performance, as long as it can do 3000+ mb/s reads and writes natively. Having said that, NVMe prices are crazy these days, so you basically pay the same for a Gen 4 drive as you would a Gen 3. In that case, you may as well go with a Gen 4 because maybe later down the line you'll throw it in a faster enclosure, or inside a PC. It's just a smarter investment at this point. DO NOT get a Gen 5 drive. Not only will you never see Gen 5 speeds, but this enclosure will have serious trouble cooling a Gen 5 drive properly. Wasted money and a bad idea all around. You also want to get yourself a nice thermal pad. The ones that come with the enclosure aren't great. I'm using a 2mm pad with my NVMe drive and it's a nice, tight fit, just as it should be. You could probably get away with 1.5mm pad, but I wouldn't go thinner than that. Gelid Ultimate thermal pads are very nice, you can find them here on Amazon for not much money. Windows users, you also MUST enable "write caching" on the device to achieve the full write speeds. If you're getting less than 1000 mb/s writes, you probably have caching disabled, which is the default on Windows 11. Go into your Device Manager, expand the "Disk drives" section, right click on the NVMe in question, go to the "Policies" tab, then select "Better performance" and then check "Enable write caching on the device". Make sure to read the disclaimers and make sure to properly "eject" the drive when you're done using it, as you can no longer just unplug it. Lastly, regardless of what the manufacturer will tell you, you don't need a Samsung 990 Pro to get full speeds with this enclosure. Any NVMe will work, some better than others. Personally I'm using a Crucial T500 because it was the same price as many other high-end drives, but it comes with DRAM and runs pretty cool, which is a bonus for this passively cooled enclosure. You could also get a WD SN580, or a WD SN770, or a TeamGroup MP44, etc. Basically look at Tom's Hardware reviews of drives and pick a solid one, it should work fine. You still want to pick one that claims read/write speeds of at least 3000 mb/s, but after that it doesn't matter too much.

Worked alright for a bout 3 mins. Using a 4TB WD Blue NVME rated at 55000MBs and TB4 port. Transfer capped out at 1.2 GB/s after it started warming up dropped down to 300mb/s transfer. Does not perform as promised will be returning Update: Ordered a replacement, Tested it Same thing. Starts out Decent at 1.2 GBps, Drops off to 300 mbps after it heats up. Drive tested in other enlcosesures and it works as intended its only these that seem to overheat and under perform.

This is an excellent NVMe enclosure. I chose the TBU405, as I feel it may have better heat dissipation than the TBU401, due to the corrugated outer casing. I honestly don't know what the difference is between the two otherwise. I have used the Samsung 980 Pro 2TB and WD Black SN 850x 2TB in the enclosure with nearly identical results on a 2023 16" M2Pro MBP with ThunderBolt 4 /USB4 ports. TEMPERATURE This enclosure gets warm. At a room temp of 21℃/70℉, (at idle) the temp of the casing is 38℃/100℉, while resting on a cork mat, (to see what temp it will idle at) which does not conduct much heat from the casing to the surface its laying on. This matters, because the only heat transfer is to ambient air around it. If I were to rest this on the MacBook Pro chassis to the right or left of the track pad or any other temp conducting surface, the temp would plummet on the ACASIS enclosure because it would transfer the heat to whatever its laying on. Any surface that readily absorbs heat from the enclosure makes an enormous difference. I don't think it's much of a concern otherwise, as NVMe SSD's can operate well up to roughly 70℃. SPEED This is about the best external solution for transferring large files. This is roughly 3x faster than nearly all NVMe external drives sold by the major SSD manufacturers due to the Thunderbolt interface. (Most of them are USB 3.x and are restricted by the 10GB/sec interface speed. You will not get max speeds on USB 3.x. Currently using with a Samsung 980 Pro 2TB with latest firmware (as recommended by ACASIS) and also tested with a WD Black SN850x 2TB (latest firmware). I thought I remember seeing ACASIS say that the latest firmware for the SN850x works with this enclosure but I don't remember where I came across that info. So take that with a grain of salt. I formatted the drive and ran some speed tests with no issue. I didn't conduct any large file transfers. Performance of these PCIe Gen 4 SSD in this enclosure wielded excellent results. I reach around 3000 MB/s on large seq. read and writes on Amorphous Diskmark. Using the included TB3 cable wielded the same results as using a brand new OWC TB4 cable. No speed issues for me with included cable. Also, no disconnects, no hiccups after transferring a little over 1TB performing backup of an old spinner. This process took around 5 hours, due to the slow conventional HD and the amount of files I transferred. This ACASIS enclosure would have been able to read/write in a minute what took the other drive over an hour to transfer. NOT KIDDING!!! FORMATTING Originally, I had formatted the Samsung 980 pro to APFS (case sensitive/Encrypted) and it wielded performance results in RND 4K QD64 Read/ lower than expected. (See Pics) (763MB vs. 1385MB) While I was somewhat disappointed in that result, I learned it was due to formatting that way. When I reformatted to just APFS, results were as expected (1385MB). Nearly double in that one metric. I thought originally that the issue might have been the SSD, not the ACASIS enclosure. Turns out it was the formatting. *Another note, is that you will not see top speeds when formatting to exFAT. It will affect your benchmarks considerably. All in all, this is an excellent solution if you need top tier performance from an external drive. I would definitely recommend. Being these Gen4 NVMe drives are capable of over 7000MB/sec I would love to see an updated enclosure. I am not sure if the bottle neck is interface speed (TB3/4 @ 40GB/sec.) or if this enclosure is using a PCIe Gen3, either way its currently the best solution for those that require as little wait time as possible using an external enclosure.