Portable external SSD face-off: ADATA SD700 vs. Samsung T3

The rise of portable external SSDs

One of the biggest improvements in computing over the past few years is the increased adoption of flash storage. While it is true that CPU and GPU technology have both improved significantly over the past years as well, it is the widespread adoption of flash memory and SSDs that I think has had the biggest impact on computing experiences. Think about how much boot up and loading time SSDs have saved you. Speed aside, SSDs also have a size advantage. Today, it is possible to cram as much as 2TB of storage onto an M.2 drive the size and weight of a stick of chewing gum. That is just incredible.

Thanks to these two significant advantages, portable external SSDs have also begun to enjoy an increase in popularity. Not only are portable external SSDs a lot quicker than traditional portable mechanical external hard disk drives, they are a lot more portable too. Most portable external SSDs will fit quite easily into pockets, but you cannot say the same for portable external hard disk drives. And because portable external SSDs have no moving parts, they are tougher and more resistant to shock too. As a result, we are beginning to see more portable external SSDs coming into the market. Today, we are going to pit Samsung’s T3 portable external SSD against one of the newest portable external SSDs on the market - ADATA’s new SD700.


The ADATA SD700 features a square design and its metal chassis is protected by a ring of rubber.

The ADATA SD700 features a square metallic case and the chassis is protected by a ring of rubber. It was designed to be one of the first dust and waterproof portable external SSDs. In fact, according to ADATA, the SD700 passes IEC IP68 specifications. This means it is dust tight and can stay submerged in 1.5 meters of water for up to an hour. Additionally, the SD700 also passes the U.S. Army MIL-STD-810G 516.6 shock and drop resistance standard. What this all means is that the SD700 is a super tough portable external SSD.

In terms of size, the ADATA SD700 is quite a bit larger than the Samsung T3, but it still remains very compact. It is still possible to fit the SD700 into the pocket of your pants, but it is going to be a bit more of a squeeze. 

No USB Type-C here or Thunderbolt 3. The ADATA SD700 connects via a USB 3.0 Micro-B port, which is of course backwards compatible with ubiquitous micro-USB 2.0 cable/connection.

The ADATA SD700 doesn’t support the newer USB Type-C connector nor does it support faster USB Type Gen 2 or Thunderbolt 3 speeds. Instead, it supports USB 3.0 and features the same single USB 3.0 Micro-B port that we see on so many other USB 3.0 portable external hard disk drives. A single USB 3.0 to USB 3.0 Micro-B cable is provided for users to connect the SD700 to their systems. The cable is of a fair length, but it is quite thick and therefore makes the SD700 more cumbersome to carry around. An integrated connector would have been a much more elegant solution, but I have yet to see an external portable SSD with such a feature.

Inside, the ADATA SD700 features a Silicon Motion SM2258 controller and uses 3D TLC NAND chips from IMFT. These are pretty standard ingredients for any mainstream SSD. Claimed performance figures according to ADATA are sequential read and write speeds of up to 440MB/s and 430MB/s respectively. That is quite comparable to the Samsung T3, which claims sequential read and write speeds of up to 450MB/s.

The supplied connecting cable is fairly long and is really thick.

Like the Samsung T3, the ADATA SD700 also supports UASP. UASP or (USB Attached SCSI) protocol is a standard aimed at improving USB 3.0 performance by transferring data and commands in separate "pipes" and executing multiple commands in parallel. So if you have a compatible system (most modern systems running Windows 8 and Mac OS X 10.8 and above should support UASP), one can expect better performance. 

Unfortunately, unlike the Samsung T3, the ADATA SD700 does not come with any built-in security features. So while the SD700 is extremely sturdy and rugged, protecting your data from unauthorized access would require users to take measures of their own.


Samsung T3

The Samsung T3 features a mostly metal construction and is really small.

The Samsung T3 was previously reviewed here, so I’m going to be brief in my introduction.

The Samsung T3 comes in a mostly metal chassis (to improve heat dispersion) and is wonderfully small. It is so small that it will slip into pockets easily. However, the same design issue that plagued the original T1 is present in the T3 as well. And that is the supplied USB cable, which is long and cumbersome to carry around. An integrated retractable USB connector would have been a much more elegant solution.

Inside, the T3 uses components found on Samsung’s SSDs. There’s the MGX controller and four NAND packages which are made up of Samsung’s new high-density 48-layer 256Gbit TLC V-NAND

Though the Samsung T3 connects via a USB Type-C port, it only supports USB 3.1 Gen 1 (5Gbps), so don't expect any improvements to performance.

The T3 also comes with a USB Type-C connector and supports the newer USB 3.1 standard, but only up to 5Gbps. This doesn’t really affect performance and or usage (since the bundled cable still terminates in a USB Type A connector), but it’s something users should take note, especially if you forgot to bring the bundled cable along with you.

The Samsung T3 has easy to setup password protection and 256-bit AES encryption to keep your data safe.

The T3 has an emphasis on security and supports 256-bit AES encryption. When you first plug the T3 into your system, the security program will run and prompt you to setup the T3 with a password. Be careful, though, the password cannot be reset on its own, so make sure you remember it. If you happen to forget your password, the only solution is to bring it down to the service center and have it reset by Samsung. This all or nothing approach sounds a little drastic, but it’s actually the most secure.

Test Setup

The drives will be tested on our updated storage testbed using the Windows 10 operating system, which has the following specifications:

  • Intel Core i7-4770K (3.5GHz)
  • ASUS Z97-Deluxe/USB 3.1 (Intel Z97 chipset)
  • 2 x 4GB DDR3-1600 memory
  • MSI GeForce 8600 GTS
  • Windows 10 Pro

We have also revised our benchmarks and the list used are as follows:

  • AS-SSD benchmark 1.8.5636.36856
  • CrystalDiskMark 5.0.2
  • PCMark 8 (Storage suite)

To keep things fair, we will be testing the ADATA SD700 and Samsung T3 with equivalent capacities. We are testing the 500/512GB variants.  Because of NAND parallelism, capacity plays a big role in determining drive performance. Generally speaking, higher capacity drives tend to perform better because the NAND controller has more memory chips to read and write to.


PCMark 8

On PCMark 8, the two drives recorded very comparable scores, with the Samsung T3 nudging slightly ahead with a score of 4946 - just a mere 19 points more. If we look at the average speed recorded, the T3 managed 229MB/s, which was about 8.5% more than the SD700’s 211.24MB/s. What this all means is that, on PCMark 8 at least, the two drives are very closely matched.


Timing Test

In our real world timing test, the results were very different from PCMark 8. While I expected the two drives to post comparable timings, the fact was that the ADATA SD700 was significantly quicker, completing the copying task in just 62 seconds - a good 12 seconds ahead of the Samsung T3.

AS SSD Results

AS SSD is a benchmark that uses non-compressible and completely random data. This takes away the advantages of SSD controllers that compress data before moving them, such as the old SandForce SF-2281 controller.

On AS SSD’s Copy Benchmark, which measures the performance of copying various types of data, the ADATA SD700 was clearly the faster drive. Across all three data types, the SD700 was at least 22% faster than the Samsung T3. 

In terms of sequential performance, the T3 was able to notch up a marginal victory of the SD700. On both sequential read and write, the T3 was about 4% to 5% quicker than the SD700.

However, the SD700 staged a convincing comeback during the more intensive 4, 64 queue depth workload. Its read performance here was nearly 50% better and its write performance was over 16% faster than the T3. Overall, it is safe to say that the SD700 is clearly the better performing drive on this benchmark.

CrystalDiskMark Results

CrystalDiskMark is an easy-to-run and quick utility to use to gauge a drive’s performance. It measures sequential read and write performance and random read and write speeds of random 4KB, 4KB (queue depth 32) and 512KB data.

On CrystalDiskMark, the ADATA SD700 was consistently quicker than the Samsung T3 across all different workloads and operations. Overall, the SD700’s sequential read and write performance was about 5% faster than the T3.

When it came to smaller 4K data blocks, the SD700’s performance advantage over the T3 grew to around 18%. It was 15% faster when it came to 4K reads and over 22% faster on 4K writes.

On the more intensive 4K, 32 queue depth workload, the SD700’s read performance was a whopping 51% better and its write performance was about 14% faster. Overall, it was a very commanding showing from the SD700.

And the Winner is…

Looking at the graphs in the earlier few pages, it is clear that the ADATA SD700 has the upper hand when it comes to performance. In most scenarios, the SD700 recorded commanding leads over the Samsung T3. So if performance is your utmost priority, my recommendation would be to go with the SD700. It is very obviously the better performer.

However, the Samsung T3 trumps the ADATA SD700 when it comes to security. The T3 has support for hardware 256-bit AES encryption and the built-in security application offers an easy way for users to secure their data. Its all-or-nothing approach might seem a little extreme, but really, it is the safest way of preventing unauthorized access of the drive.

The ADATA SD700 is the winner thanks to its rugged design and superior drive performance.

Picking a winner between the two is hard, but I think the ADATA SD700 is the better all-rounder. Its performance advantage over the Samsung T3 is not be scoffed at. In some instances, it was as much as over 50% faster. And in our real world timing test, it was a good 16% faster than the T3, and that’s a very significant margin. 

In addition, the SD700 is also designed to be more rugged than the T3 and that is an important consideration for any portable external drive. Granted, no one is going to intentionally subject their precious portable external drives to dusty environments or any bodies of liquids, but it is good to know that if the situation calls for it, the drive will be more than up to the task. Bearing all of this in mind, I think the SD700 more than justifies its higher S$329 asking price.

As for the SD700’s security shortcomings? I would recommend using a trusted security application to create an encrypted disk image on the SD700 as a workaround to the drive’s lack of built-in security features. Mac users can simply use OS X’s and macOS’ built-in Disk Utility app to create an encrypted disk image. Windows users can check out apps like VeraCrypt and DiskCryptor.

The Samsung T3 is no slouch too, especially if you value portability, security and ease of use.

That said, the Samsung T3 is by no means a bad drive. In the grand scheme of things, it is still a very quick drive and the SD700 can’t compete with it if portability is your utmost priority. And at S$299, it is slightly less expensive too.

Here’s the breakdown of the two drives’ ratings.

Score Breakdown



Samsung T3