By David Ramsey

Manufacturer: Samsung
Product Name: Portable SSD T5 1TB
Part Number: MU-PA1T0B/AM
UPC: 887276226316
Price As Tested: $349.99 (Newegg | Amazon)

Full Disclosure: Samsung Electronics Co. Ltd. provided the product sample used in this article.

Solid state memory, while remaining significantly more expensive that traditional mechanical hard disks, continues to encroach on their territory. Inexpensive and high-capacity bus-powered USB external drives are even being challenged by external SSDs, for consumers who appreciate the advantages of much higher performance, smaller size, and greater reliability they afford. Samsung has been a pioneer in this field with their Samsung Portable SSD T3 external drives, and today Benchmark Reviews checks out their latest product, the 1 terabyte Portable SSD T5.

Capacity	1TB
Interface	USB 3.1 SSP with UASP
Form Factor	Custom, 74mm x 57.3mm x 10.5mm
NAND	TLC NAND
Max transfer speed	540MB/s (USB 3.1 Gen 2)
Interface	USB Type C, USB Type A
Warranty	3 years

No matter how fast your processor, memory, or video card is, your computer will still be limited by its slowest component: the hard disk. While hard disk speed has improved tremendously since the “early days”, with large caches and 10,000RPM spindle speeds, even the fastest hard disk’s performance is glacial compared to the rest of the computer. The situation only gets worse with modern pre-emptive multitasking operating systems, where dozens of threads are running simultaneously and competing for your disk’s limited response time and bandwidth.

Consider: the average time to move a high-performance hard disk’s read/write head to a new track will be less than 10ms, which seems pretty fast. But your CPU is galloping along at billions of cycles per second, and will spend a significant amount of its time just waiting for the hard disk to fulfill its last request. Hard disk performance has plateaued in the last few years, running up against the physical limitations of spindle speeds, magnetic media density, and head servomotor performance. At the end of the day, disks are limited by the fact that they’re comprised of physical, moving parts.

With no moving parts, Solid State Drive technology removes this bottleneck. The difference an SSD makes to operational response times and program speeds is dramatic: while a faster video card makes your games faster, and a faster processor makes compute-bound tasks faster, Solid State Drive technology makes your entire system faster, improving initial response times by more than 450x (45,000%) for applications and Operating System software, when compared to their mechanical HDD counterparts. The biggest mistake PC hardware enthusiasts make with regard to SSD technology is grading them based on bandwidth speed alone. File transfer speeds are important, but only so long as the operational I/O performance can sustain that bandwidth under load.

As we’ve explained in our SSD Benchmark Tests: SATA IDE vs AHCI Mode guide, Solid State Drive performance revolves around two dynamics: bandwidth speed (MB/s) and operational performance I/O per second (IOPS). These two metrics work together, but one may be more important than the other. Consider this analogy: bandwidth determines how much cargo a ship can transport in one voyage, and operational IOPS performance is how fast that ship moves. By understanding this and applying it to SSD storage, there is a clear importance set on each variable depending on the task at hand.

For casual users, especially those with laptop or desktop computers that have been upgraded to use an SSD, the naturally quick response time is enough to automatically improve the user experience. Bandwidth speed is important, but only to the extent that operational performance meets the minimum needs of the system. If an SSD has a very high bandwidth speed but a low operational performance, it will take longer to load applications and boot the computer into Windows than if the SSD offered a higher IOPS performance.

The Samsung T5 Portable SSD we’re testing is the 1TB model, which sells online for $349.99 (Newegg | Amazon) This USB 3.1 External SSD is available in four capacities: 250GB, 500GB, 1TB, and 2TB. The Samsung Portable SSD T5 is a simple black rectangle with rounded edges.There are no activity or power indicators.

There’s not much on the back of the drive, either. Come to think of it, which is the back and which is the front?

The USB 3.1 Type C connector is the only physical feature on the drive exterior. Although it’s not visible in this image, there’s a (dim) blue activity light to the right of the USB connector.

The drive comes with a brief “Getting Started” manual, and cables to connect to either USB 3 Type A or Type C ports. With the proliferation of laptop computers that have only Type C ports, such as Apple’s Macbooks and HP’s Spectre, it’s nice to see a separate cable for Type C so you don’t need an adapter dongle.

Although standard bus-powered external 2.5″ drives are small, the Samsung Portable SSD T5 is much smaller.

Samsung’s drive does come with optional security software that will lock the drive with a password. When you initially plug the drive in, only a small partition with Windows, Mac, and Android versions of the security software is available; you can’t mount the main drive partition without the password (if you set one). If you set the password and forget it, you must return the drive to Samsung to be reformatted.

Normally at this point I’d open the drive up and examine the actual hardware– controller, memory, etc.– but the T5 is a sealed unit, so the only way I can evaluate it is by its performance. Let’s see how it performs in the next section.

When we test storage devices, the two main metrics to consider are access time and transfer rate. Simply put, access time is the time is takes the storage device to start delivering data once the request has been received, while transfer rate is how fast (megabytes per second) the data comes once the transfer operation begins. With a hard disk, data transfer cannot begin until the disk’s head servo physically moves the read/write head to the correct track, and the rotation of the disk brings the designated sector under the head. Although modern servos are very fast, in the best case you’re still looking at several milliseconds to do this, while an SSD’s access time is always under a millisecond. The disadvantage is even worse if the data isn’t all in a contiguous space on the disk, since the head will have to be repositioned on the fly, leading to more delays.

Early consumer SSDs actually had slower transfer rates than the best hard disks, although their instantaneous access times more than made up for it. The zenith of consumer hard disk performance was probably reached in 2012 with the release of the Western Digital Velociraptor 1 terabyte disk. Spinning at 10,000RPM, this disk could under ideal circumstances (i.e. a synthetic bandwidth test) reach a sequential transfer rate of over 230MB/s. Keep this figure in mind as you read this review.

Early on in our SSD coverage, Benchmark Reviews published an article which detailed Solid State Drive Benchmark Performance Testing. The research and discussion that went into producing that article changed the way we now test SSD products. Our previous perceptions of this technology were lost on one particular difference: the wear leveling algorithm that makes data a moving target. Without conclusive linear bandwidth testing or some other method of total-capacity testing, our previous performance results were rough estimates at best.

Our test results were obtained after each SSD had been prepared using DISKPART or Sanitary Erase tools. As a word of caution, applications such as these offer immediate but temporary restoration of original ‘pristine’ performance levels. In our tests, we discovered that the maximum performance results (charted) would decay as subsequent tests were performed. SSDs attached to TRIM enabled Operating Systems will benefit from continuously refreshed performance, whereas older O/S’s will require a garbage collection (GC) tool to avoid ‘dirty NAND’ performance degradation.

It’s critically important to understand that no software for the Microsoft Windows platform can accurately measure SSD performance in a comparable fashion. Synthetic benchmark tools such as ATTO Disk Benchmark and Iometer are helpful indicators, but should not be considered the ultimate determining factor. That factor should be measured in actual user experience of real-world applications. Benchmark Reviews includes both bandwidth benchmarks and application speed tests to present a conclusive measurement of product performance.

Motherboard: MSI Z170A GAMING M7 Socket LGA 1151
Processor: 4.0 GHz Intel Core i7-6700K Skylake CPU
System Memory: 16GB DDR4 2133MHz
Operating System: Microsoft Windows 10 Pro

The following storage hardware has been used in our benchmark performance testing, and may be included in portions of this article:

AS SSD Benchmark 1.6.4067.34354: Multi-purpose speed and operational performance test
ATTO Disk Benchmark 2.46: Spot-tests static file size chunks for basic I/O bandwidth
CrystalDiskMark 3.0.1a by Crystal Dew World: Sequential speed benchmark spot-tests various file size chunks
Iometer 1.1.0 (built 08-Nov-2010) by Intel Corporation: Tests IOPS performance and I/O response time
Finalwire AIDA64: Disk Benchmark component tests linear read and write bandwidth speeds
Futuremark PCMark Vantage: HDD Benchmark Suite tests real-world drive performance

This article utilizes benchmark software tools to produce operational IOPS performance and bandwidth speed results. Each test was conducted in a specific fashion, and repeated for all products. These test results are not comparable to any other benchmark application, neither on this website or another, regardless of similar IOPS or MB/s terminology in the scores. The test results in this project are only intended to be compared to the other test results conducted in identical fashion for this article.

Testing Note on USB 3 ports: When USB 3.0 debuted in 2010, its 5 gigabits per second (5Gb/s) transfer rate was over 10 times faster than USB 2.0’s 480Mb/s. Since then, the USB 3.0 standard has been extended with the USB 3.1 and Type C connector enhancements. To make things even more confusing, there’s USB 3.1 Gen 1 (still at 5Gb/s) and USB 3.1 Gen 2 (10Gb/s).

Without going into too much detail, here are the things to keep in mind:

USB 3 on a standard USB port (with the blue plastic connector) will always be limited to 5Gb/s
A USB C port, the small reversible-connector port first seen on Apple’s Macbook and now spreading to notebooks and desktops in the PC world, may be either USB 3.1 Gen 1 (5Gb/s) or USB 3.1 Gen 2 (10Gb/s)
There is no way to visually distinguish a Gen 1 port from a Gen 2 port; the performance depends on the chipset driving the port. However, computers that implement Gen 2 ports will typically label the port with the official specification of “USB SuperSpeed+”.

Since few computers at the time of this review support the SuperSpeed+ interface and protocol, we’ll be testing the drive both with a SuperSpeed+ port at 10Gb/s as well as a standard USB 3 port at 5Gb/s. In the accompanying bar charts, the benchmarks run on the 10Gb/s port will be flagged with “(10G)”.

Alex Schepeljanski of Alex Intelligent Software develops the free AS SSD Benchmark utility for testing storage devices. The AS SSD Benchmark tests sequential read and write speeds, input/output operational performance, and response times.

AS-SSD Benchmark uses compressed data, so sequential file transfer speeds may be reported lower than with other tools using uncompressed data. For this reason, we will concentrate on the operational IOPS performance in this section.

Beginning with sequential transfer performance, the Samsung Portable SSD T5 solid state drive produced 428MB/s for sequential reads and 418MB/s for sequential writes. The 4K-64 thread test we concentrate on in this benchmark produced only 105MB/s reads and 156MB/s writes.

Samsung Portable SSD T5 (5Gb/s)

At 10Gb/s, the drive’s performance improves in some measures, but declines dramatically in others. For example, note the massive drop in sequential read performance, but significant increase in sequential write performance. The 4K-64 thread read score dropped by almost 60%.

The chart below summarizes AS-SSD 64-thread 4KB IOPS performance results among a variety of enthusiast-level SSDs. The MU-PA1T0B returns a low score relative to the internal SSDs that comprise the bulk of the chart, but handily outperforms the previous generation Portable SSD T3 as well as the MyDigitalSSD BOOST drive…but only when connected to a standard 5Gb/s USB 3.0 port.

In the next section, Benchmark Reviews tests transfer rates using ATTO Disk Benchmark.

The ATTO Disk Benchmark program is free, and offers a comprehensive set of test variables to work with. In terms of disk performance, it measures interface transfer rates at various intervals for a user-specified length and then reports read and write speeds for these spot-tests. There are some minor improvements made to the 2.46 version of the program that allow for test lengths up to 2GB, but all of our benchmarks are conducted with 256MB total length. ATTO Disk Benchmark requires that an active partition be set on the drive being tested. Please consider the results displayed by this benchmark to be basic bandwidth speed performance indicators.

1TB Samsung T5 Benchmark Results (5Gb/s)

At 5Gb/s, the T5’s 457MB/s reads and 462MB/s writes are impressive for a USB device, but still below any internal drive. Connecting the drive to a SuperSpeed+ port actually decreases read performance slightly to 456MB/s while increasing write performance by about 7% to 492MB/s. The slight dropoff in transfer rate with 2048-kbyte and larger block sizes is something I haven’t seen before.

Again, compared mainly to internal SSDs, the Samsung T5 1TB is somewhat slower, although it is faster than the previous generation T3 and the MyDigitalSSD BOOST at 5Gb. However, when connected to a USB 3.1 Gen 2 port, the BOOST, leveraging off its internal RAID architecture, retains its position as the fastest non-PCI-E SSD we’ve ever tested.

In the next section, Benchmark Reviews tests sequential performance using the CrystalDiskMark 3.0 software tool…

CrystalDiskMark 3.0 is a file transfer and operational bandwidth benchmark tool from Crystal Dew World that offers performance transfer speed results using sequential, 512KB random, and 4KB random samples. For our test results chart below, the 4KB 32-Queue Depth read and write performance was measured using a 1000MB space. CrystalDiskMark requires that an active partition be set on the drive being tested, and all drives are formatted with NTFS on the Intel P67 chipset configured to use AHCI-mode. Benchmark Reviews uses CrystalDiskMark to illustrate operational IOPS performance with multiple threads. In addition to our other tests, this benchmark allows us to determine operational bandwidth under heavy load.

CrystalDiskMark uses compressed data, so sequential file transfer speeds are reported lower than with other tools using uncompressed data. For this reason, we will concentrate on the operational IOPS performance in this section.

CrystalDiskMark 3.0 reports sequential speeds reaching 445MB/s reads and 448 MB/s writes.

1TB Samsung T5 Portable SSD CrystalDiskMarkResults (5Gb/s)

Running the benchmark at 10Gb/s produces mixed results. Significant improvements are seen in each aspect of this test except the 4K transfers at a queue depth of 32: these scores decline drastically.

1TB Samsung T5 Portable SSD CrystalDiskMarkResults (10Gb/s)

The chart below summarizes 4K random transfer speeds with a command queue depth of 32. The Samsung T5 at 5Gb/s takes the crown as the best performing external SSD in this metric.

In the next section, we continue our testing using Iometer to measure input/output performance…

Iometer is an I/O subsystem measurement and characterization tool for single and clustered systems. Iometer does for a computer’s I/O subsystem what a dynamometer does for an engine: it measures performance under a controlled load. Iometer was originally developed by the Intel Corporation and formerly known as “Galileo”. Intel has discontinued work on Iometer, and has gifted it to the Open Source Development Lab (OSDL). There is currently a new version of Iometer in beta form, which adds several new test dimensions for SSDs.

Iometer is both a workload generator (that is, it performs I/O operations in order to stress the system) and a measurement tool (that is, it examines and records the performance of its I/O operations and their impact on the system). It can be configured to emulate the disk or network I/O load of any program or benchmark, or can be used to generate entirely synthetic I/O loads. It can generate and measure loads on single or multiple (networked) systems.

To measure random I/O response time as well as total I/O’s per second, Iometer is set to use 4KB file size chunks over a 100% random sequential distribution at a queue depth of 32 outstanding I/O’s per target. The tests are given a 50% read and 50% write distribution. While this pattern may not match traditional ‘server’ or ‘workstation’ profiles, it illustrates a single point of reference relative to our product field.

All of our SSD tests used Iometer 1.1.0 (build 08-Nov-2010) by Intel Corporation to measure IOPS performance. Iometer is configured to use 32 outstanding I/O’s per target and random 50/50 read/write distribution configuration: 4KB 100 Random 50-50 Read and Write.icf. The chart below illustrates combined random read and write IOPS over a 120-second Iometer test phase, where highest I/O total is preferred. Again, connecting the drive to a 10Gb/s port results in slower performance than when the drive is connected to a 5Gb/s port, although even that number is better than the one returned by the Samsung T3.

Here we see a repeat of the “5Gb/s beats 10Gb/s” results we’ve seen in previous tests.

In our next section, we test linear read and write bandwidth performance and compare the speed of MyDigitalDiscount’s external SSD against several other top storage products using the AIDA64 Disk Benchmark.

Many enthusiasts are familiar with the Finalwire AIDA64 benchmark suite, but very few are aware of the Disk Benchmark tool available inside the program. The AIDA64 Disk Benchmark performs linear read and write bandwidth tests on each drive, and can be configured to use file chunk sizes up to 1MB (which speeds up testing and minimizes jitter in the waveform). Because of the full sector-by-sector nature of linear testing, Benchmark Reviews endorses this method for testing SSD products, as detailed in our Solid State Drive Benchmark Performance Testing article. One of the advantages SSDs have over traditional spinning-platter hard disks is much more consistent bandwidth: hard disk bandwidth drops off as the capacity draws linear read/write speed down into the inner-portion of the disk platter. AIDA64 Disk Benchmark does not require a partition to be present for testing, so all of our benchmarks are completed prior to drive formatting.

Linear disk benchmarks are superior bandwidth speed tools because they scan from the first physical sector to the last. A side affect of many linear write-performance test tools is that the data is erased as it writes to every sector on the drive. Normally this isn’t an issue, but it has been shown that partition table alignment will occasionally play a role in overall SSD performance (HDDs don’t suffer this problem).

At 10Gb/s, the average read performance ticks up significantly, rising about 16% from 403.9MB/s to 468.7MB/s, with over 500MB/s in some places. It’s interesting that this test shows a much greater variance in performance, although at only about 6% between the maximum and minimum transfer rates, it’s not something that would be noticeable outside of a benchmark.

We run the AIDA64 linear read and write tests with a 1M block size. Charted above, read performance on the BOOST 1RB external SSD returned average speeds of 400.7MB/s.

AIDA64 linear write-to tests were next…

If you’ve been following our SSD reviews over the years, this one chart will show you just how much SSD controllers have advanced. SSDs hate linear writes, since their RAM or single-cell caches fill and performance drops drastically. It’s not unusual to see very frenetic “sawtooth” graphs for this test. Here, throughput doesn’t drop noticeably until just over 200GB of data has been written, and the falloff is relatively small and very well managed.

Moving to a USB 3.1 Superspeed+ port increases peak write speed significantly, but a more dramatic– although still very smooth and well-managed– dropoff drags down the average write speed.

When connected to a 10Gb/s port, the Samsung T5 acquits itself well, being beaten only by the BOOST in the external drive category.

In the next section we use PCMark Vantage to test real-world performance…

PCMark Vantage is an objective hardware performance benchmark tool for PCs running 32- and 64-bit versions of Microsoft Windows 7. PCMark Vantage is well suited for benchmarking any type of Microsoft Windows 7 PC: from multimedia home entertainment systems and laptops, to dedicated workstations and high-end gaming rigs. Benchmark Reviews has decided to use the HDD Test Suite to demonstrate simulated real-world storage drive performance in this article.

PCMark Vantage runs eight different storage benchmarks, each with a specific purpose. Once testing is complete, results are given a PCMark score while and detailed results indicate actual transaction speeds.

The Vantage test is one of the few tests that show a consistent improvement in performance for the T5 drive when it’s connected to a USB SuperSpeed+ 3.1 interface.

In the next section, I’ll present my final thoughts and conclusion.

IMPORTANT: Although the rating and final score mentioned in this conclusion are made to be as objective as possible, please be advised that every author perceives these factors differently at various points in time. While we each do our best to ensure that all aspects of the product are considered, there are often times unforeseen market conditions and manufacturer changes which occur after publication that could render our rating obsolete. Please do not base any purchase solely on our conclusion, as it represents our product rating specifically for the product tested which may differ from future versions.

As we’ve seen with the MyDigitalSSD BOOST 1TB drive, sequential read and write performance improves a bit when the Samsung Portable SSD T5 drive is connected to a 10Gb/s Type C port, but random and queued scores drop dramatically:

Test	5Gb/s	10Gb/s	% Change
AS-SSD Read	104.8MB/s	39.9MB/s	-62
AS-SSD Write	156.3MB/s	112.0MB/s	-28
ATTO Read	462MB/s	492MB/s	+6.5
ATTO Write	457MB/s	483MB/s	+5.7
Crystal Diskmark Read	178.8MB/s	36.3MB/s	-80
Crystal Diskmark Write	181.7MB/s	120.8MB/s	-34
IOMeter	47870 iOPS	11521 iOPS	-76
AIDA64 Read	404MB/s	469MB/s	+16
AIDA64 Write	364MB/s	343MB/s	-5.8
Vantage Overall	55070	57861	+5.1

In fact, the overall performance hit when the Samsung Portable SSD T5 is connected to a USB 3.1 SuperSpeed+ port is so dramatic that I’d recommend you never do this if you have the option of using a slower port. Since the Samsung drive in this review is a sealed unit, I can’t speak to the architecture of the device, but this much performance drop is still surprising.

Flash memory prices have been very volatile of late, and while the price of internal SATA SSDs hasn’t changed much, for whatever reason the price of external SSDs has risen dramatically, making them less attractive as a storage option. When we reviewed the Transcend ESD400 512GB external SSD in August, 2016, it was $184.99; the same drive now sells for $360.00. Similarly, the MyDigitalSSD BOOST 1TB drive that was $262.12 direct from the manufacturer in our December 2016 review is now $440.86. Curiously, Samsung’s Portable SSD T3 512GB bucks the trend: it was $219.99 in February of 2016, and is now $218.00.

At $349.99, the 1TB version of the Samsung Portable SSD T5 priced similarly to other external SSDs of the same capacity, and significantly less than the $429 Samsung oddly charges for the 1TB version of the previous-generation T3 drive.

Impressively, the Portable SSD T5 beat the MyDigitalSSD BOOST 1TB drive in every single benchmark except those concerned with pure sequential I/O, where the latter’s RAID architecture gave it the extra bandwidth needed to fully utilize the 10Gb/s SuperSpeed+ USB 3.1 interface. This metric will help you make a choice: if your primary use will be large file transfer, go with the BOOST; otherwise, the T5 wins, dramatically in some cases.

Although the T5’s performance is impressive, its $349.99 (Newegg | Amazon) price makes it a very hard sell when any office supply store will sell you the same terabyte of external, USB-powered storage for $60 or less; and considering how often external drives like this are used for backup duty, the lack of included backup software is surprising. However, for the few users who really need the exception performance from an external drive that the T5 provides, it’s the way to go.

+ Much higher performance than USB-powered external hard disk drives
+ Supports 10Gb/s USB-C SuperSpeed+
+ Graceful handling of performance dropoff with extended linear writes
+ Comes with USB Type C cable for direct connection to newer computers sans dongle

– Very expensive compared to traditional external drives
– No backup software

Performance: 9.00
Appearance: 8.00
Construction: 9.50
Functionality: 8.00
Value: 7.75

Recommended: Benchmark Reviews Seal of Approval.

COMMENT QUESTION: Which brand of SSD do you trust most?

By David Ramsey

Samsung Portable SSD T5 (5Gb/s)

1TB Samsung T5 Benchmark Results (5Gb/s)

1TB Samsung T5 Portable SSD CrystalDiskMarkResults (5Gb/s)

1TB Samsung T5 Portable SSD CrystalDiskMarkResults (10Gb/s)

Recommended: Benchmark Reviews Seal of Approval.

By David Ramsey

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