The big storage veteran SanDisk, now a property of Western Digital Corporation (WDC), is jumping into the suddenly hot game of 3D TLC NAND. That may sound like the nerdiest parlor game ever, but it's actually just the latest trend in solid state drive (SSD) technology—and where the volume sales in the SSD market are moving. The new Ultra 3D SSD ($284.99 in the 1TB version we tested) is actually the same drive underlying its parent's WD Blue 3D NAND SSD (which we reviewed in parallel). It's sold under the SanDisk badge for SanDisk brand loyalists, with the two companies now under one virtual roof. If you were peel off each SSD's outer shell, though, you'd find the same core components inside.
This new SSD is the SanDisk brand's first spin at this new "3D" type of memory, but it is not SanDisk's first model to make use of TLC NAND. The SanDisk Ultra II we reviewed a while back used TLC, in the SSD pre-Cambrian era of 2015. The 3D variety is a new type of TLC NAND flash, though. In an architectural nutshell: The actual memory cells are stacked vertically, instead of laid down side-by-side like on the previous drive. That allows for space savings and other efficiencies. (Of course, all of this is invisible from the design of the drive itself.)
Not only is the flash stacked vertically now, but SanDisk is riding on the leading edge of SSD tech with its 64-layer design. That said, since this is a drive based on budget-minded TLC memory, the Ultra 3D SSD is coming to market not as a fire-breathing, benchmark-busting flagship drive but rather a midrange, affordable, high-capacity model targeting home users, PC builders, budget-minded enthusiasts, and business users. This line is basically a step above entry-level SSDs, with some advanced technology, excellent endurance, competitive performance, and an affordable price.
Similar Products
Crucial BX300 (240GB)
Samsung SSD 850 EVO M.2 (250GB)
Samsung SSD 960 EVO
Intel Optane SSD 900P Series (280GB)
Samsung SSD 850 EVO (4TB)
Design and Features
Unlike its WD Blue counterpart, the Ultra 3D is available only in the 2.5-inch, 7mm-thick form factor. In contrast, the WD Blue 3D comes in both ordinary 2.5-inch kit and in the newer M.2 "gumstick" format. The good news is that most SSD buyers need a 2.5-inch drive in an upgrade, as only the newest desktop motherboards and laptops offer support for the M.2 form factor. (Many thin laptops use M.2 nowadays, but more the issue is getting inside those laptops to effect any kind of component-level upgrade.) This will allow the drive to be used with any desktop PC on the market with a free SATA port, or in a thicker laptop with an older SATA connection and a 2.5-inch drive bay, as opposed to an M.2 slot.
SanDisk offers the Ultra 3D drive in four capacities: 250GB, 500GB, 1TB, and 2TB. The last is the first 2TB drive offered by SanDisk. It is also a sign of the times: NAND flash has become affordable enough that a company would even consider launching such a capacity in a non-enterprise-grade SSD. Such high-capacity drives used to be price-prohibitive and well beyond $1,000, but the 2TB drive was "only" $549 (the street price) at the time we wrote this in early September 2017.
Inside the Ultra 3D is SanDisk's own flash, manufactured in a joint development with Toshiba, combined with a Marvell controller. As we wrote in the introduction, this is 3D TLC flash with a 64-layer design, which is the most layers possible given current technology. Intel, too, just released its own 64-layer 3D SSD a short while ago, so this is literally the very latest in mainstream-market SSD tech.
The Ultra 3D SSD is specified by SanDisk to hit a maximum of 560MB per second on sequential reads, and 530MB per second for sequential writes, which is right-on for a Serial ATA drive. The theoretical ceiling on SATA allows for only 600MB per second; once you trim off a bit of performance due to overhead on the channel and other "not in a perfect vacuum" factors, you end up with numbers like these. They are common for a late-model SATA drive, in other words.
Like most other TLC drives on the market, the SanDisk Ultra 3D uses what is known as a "pseudo-SLC" cache, in SanDisk's parlance called "Ncache 2.0." This is used to overcome the weakness of TLC flash when it comes to write operations, and it mostly works quite well. The drive writes to its "SLC-like" cache first, then when the drive is idle, it transfers the data to the flash array instead of writing in real-time from it.
This behavior helps for smaller data writes (in the neighborhood of a few gigabytes), but if you need to write a hunk of data in one shot that is bigger than the cache, you'll see performance degrade considerably. This approach was a considered one by SanDisk/WD, as this usually isn't a problem for home users; most of them don't need to write, say, single giant 10GB files very often. The size of the cache varies, too, and it's never really clear how large it is at any given time, and it also varies according to how much free space the drive has.
One of the potential main advantages of this drive's 3D NAND design is improved endurance. Since the bits of flash are stacked vertically instead of side-by-side, they can be a bit larger than they would be otherwise, which allows for more room to operate (and thus narrower tolerances necessary) in the design. It also reduces interference between cells. This allows for increased endurance, and on this drive the numbers are indeed impressive. According to SanDisk, the 250GB version is good for 100TB of data written to it before it starts to show wear (i.e., decommissioning of some of the cells), which no ordinary user would ever be able to achieve in the drive's three-year warranty period. Going up the scale, the 500GB version can handle 200TB, the 1TB is rated for 400TB, and the 2TB drive is good for 500TB. Unless the drives were deployed in a server situation, with constant writing by a host of users, no ordinary single user would ever be able to write enough data to the drives to even approach any of these numbers. So, suffice it to say, that the endurance, if it's even close to the rated figures, is more than ample.
To help you manage your SSD, SanDisk includes its rudimentary SSD Dashboard software. The software primarily lets you check the health of the drive, update its firmware, secure-erase it (the equivalent of a factory reset), check out its performance, and access support features. It also includes cloning software so you can copy your existing drive to the Ultra 3D, a nice extra that not every SSD maker includes. The download locations come on a small slip that comes with the drive...
As far as pricing goes, since the Ultra 3D SSD uses TLC flash, it's pretty affordable relative to the market. According to the early September 2017 pricing on Amazon, here's how it breaks down...
Drive Capacity |
List Price |
250GB |
$99.99 |
500GB |
$164.99 |
1TB |
$284.99 |
2TB |
$549.99 |
That's aggressive pricing, and Amazon has already undercut the official MSRP on this drive, so clearly SanDisk is not messing around in its attempt to dethrone the Samsung SSD 850 EVO as the 2.5-inch TLC drive of choice. It's actually less expensive than the Samsung at both 500GB and 1TB, which is a relative pricing situation rarely seen, given how competitive Samsung is in this arena and how it can employ its economies of scale to make life very difficult for its SSD competition.
The Samsung drive still has a longer warranty, at five years, but given the high endurance ratings of these 3D NAND drives, that doesn't seem quite as big of an issue as it was a few years ago. The Samsung drive does have an overall better supporting software bundle, too, but given how infrequently most people actually access SSD utility software, that's also a pretty minor issue.
The real issue beyond pricing parity, of course, is performance. Oh, what a perfect segue.
Performance Testing
If you're new to the world of solid-state drives, a few things are worth noting when it comes to performance. For starters: If you're upgrading from a standard spinning hard drive, any modern SSD will be a huge improvement, speeding up boot times and making programs launch faster. Most of today's high-end 2.5-inch SSDs make use of a specific interface, SATA 3.0 (also called "6Gbps SATA"), to achieve maximum speed versus older, but still common, SATA 2 ports, which top out at 300MB per second. We test all our SSDs on a SATA 3.0-equipped test-bed PC to show their full performance abilities. To get the most speed possible from modern drives, you'll need a system with SATA 3.0 capability, as well.
If your system is based on a recent Intel chipset, later than those supporting 2nd-Generation "Sandy Bridge" processors (or one of the newer AMD chipsets), your laptop or desktop almost certainly has this interface. Be sure before buying, though. If your system is creaky and doesn't have SATA 3.0 support, there's little point in paying a premium for a drive with the maximum possible performance. SATA 3.0-capable drives will work just fine with previous-generation SATA ports, and there's scant reason to pay extra for drive speed that your system can't take advantage of. Any basic current SSD will work just as well, in that SATA 3.0-less scenario.
AS-SSD (Sequential Read & Write Speeds)
This test uses the AS-SSD benchmark utility, which is designed to test SSDs, as opposed to traditional spinning hard drives. It measures a drive's ability to read and write large files. Drive makers often quote these speeds as a theoretical maximum on the packaging or in advertising.
Sequential speeds are important if you're working with very large files for image or video editing, or you play lots of games with large levels that take a long time to load with traditional hard drives. We secure-erase all SSDs before running this test...
The read portion of this test isn't particularly insightful, since SSDs have been able to saturate the SATA bus for a few years now. So, as you can see, almost all of the drives perform similarly. The SanDisk drive was right in the thick of it with its showing of 510MB per second. That's to be expected from pretty much any modern SSD, though, so the SanDisk gets a score of "pass."
When it comes to write speeds, things are a bit less uniform, and the wheat begins to separate from the chaff...
As you can see in the chart, though the SATA bus has a maximum bandwidth cap of 600MB per second, the fastest drive we tested in this lot hit only 500MB per second, and the SanDisk Ultra 3D wasn't too far behind that. It's interesting that the SanDisk drive is just a tiny bit ahead of the other new entry in the 64-layer 3D TLC NAND drive race, Intel's SSD 545s drive. This shows that in this test, the flash made by Intel is quite close in performance made by the joint Toshiba/SanDisk fab. Overall, this is a pretty competitive result from the SanDisk 3D drive, placing it adjacent to the Samsung SSD 850 EVO, which also uses 3D TLC NAND.
AS-SSD (4K Read & Write Speeds)
This test, also a part of the SSD-centric AS-SSD benchmark, measures a drive's ability to traffic small files. Often overlooked, 4K performance, particularly 4K write performance, is important when it comes to boot speed and program launch times.
When booting up and launching programs, many tiny files get accessed and edited frequently. The faster your drive can write and read these kinds of files (especially dynamic link library, or DLL, files in Windows), the faster your OS will "feel." Since small files like these get accessed much more frequently than large media or game-level files, a drive's performance on this test will have a greater impact on how fast a drive feels in everyday use.
It's interesting that the SanDisk drive and the WD show some daylight between in this test, despite being the same under the skin. Still, the SanDisk landed solidly in the middle of the pack here, sandwiched between two entry-level SSDs from Samsung and Crucial, so while it's not a super-strong showing, it's about where it should be as a TLC-based drive.
This chart indicates that the majority of late-model mainstream SSDs are similar when it comes to writing small files. Nine of the 12 drives in our chart were all within 6MB per second of each other, forming a solid line straight up the middle of the chart and showing performance parity. The SanDisk Ultra 3D is right near the top of this grouping, a good showing for this TLC drive. It is interesting, though, once again, how the WD M.2 drive was a touch faster.
Anvil's Storage Utilities
Anvil's Storage Utilities is, like AS-SSD, an SSD-specific set of drive-benchmarking tests. We'll report here the Overall Score, which is derived from the Read and Write scores with the utility running at default settings. (That is, with 100 percent incompressible data.) The drive was secure-erased before the test was run.
The SanDisk Ultra 3D performed quite well in Anvil testing, landing near the top of our benchmark chart and once again performing slightly better than its 3D TLC rival from Intel. Its score of 4,892 was good enough for fourth-fastest SSD of the lot in this test, albeit by a relatively small margin as several drives are stacked up quite close to one another at the top of the chart. Indeed, in this test the Ultra 3D is only about 150 points behind the fastest drive overall, the MLC-based Samsung SSD 850 Pro, almost within the margin of error. That's darn good for an affordable SATA SSD. Once again, the WD 3D drive was a smidge faster.
Crystal DiskMark (QD32 Testing)
Crystal DiskMark uses incompressible data for testing, which stresses most modern SSDs quite a bit since they rely on data compression to achieve their maximum level of performance. This particular test is designed to replicate the duties of an SSD located inside a Web server, as it's asked to perform a smattering of small reads, 4K in size. While it's reading these files, a queue of 32 outstanding requests is lined up (a "queue depth" 32 requests deep). That's typical of a high-volume Web server, which has to fulfill requests coming in at the same time from various clients.
The SanDisk Ultra 3D once again landed squarely in the middle of this chart, showing it can hang with the big boys, if not topple them. It was noticeably closer to the WD Blue 3D this time around, too. In this test, nothing can touch Samsung's combination of its own flash and controller, but the Toshiba/SanDisk flash and Marvell controller came close, so that speaks well of WD's engineering and firmware.
On to the write test...
The SanDisk Ultra 3D and WD Blue 3D aligned here, surprisingly near the upper echelon of our leaderboard in this grueling benchmark, taking fourth and fifth place respectively. This particular task is one of the most demanding things an SSD can do, so it's comforting to know that even though this test is a bit unrealistic for a mainstream drive (since a consumer will never have a queue of 32 outstanding requests), the SanDisk Ultra 3D was up to the task. Like in the other tests, it's not the fastest drive, but up there close.
PCMark 7 Secondary Storage Test
Our last test is the PCMark 7 Secondary Storage Test. This holistic trial simulates everyday drive accesses in a Windows environment.
This is another one of those tests that gives you a great visual representation of just how close modern SATA SSDs are in real-world performance. Most of this recent lot of drives we've tested fared similarly in this test, with the SanDisk Ultra 3D missing out on the top spot by a trivial margin. That result essentially means all of these drives are close enough that it's a tie for bragging rights; they're all reasonably fast, as far as SATA drives go, and the SanDisk SSD is clearly not a slouch.
Conclusion
More than two years after the release of the Samsung SSD 850 EVO series of SSDs, we're finally starting to see a few challengers to its supremacy, thanks to the adoption of 3D NAND by some of its rivals. This new type of memory has given the business a shot in the arm, as it has lead to new drives with impressive endurance, performance, and capacity while also allowing for lower prices. Though SATA drives are seen as "legacy" devices these days, due to the age of the standard (and the fact that PCI Express has muscled into the high end of the market), drives like the SanDisk Ultra 3D (and the WD Blue 3D) are quite close to what we've all been asking for in the SATA-SSD world for a while now, in terms of performance, endurance, and pricing.
Though the SanDisk Ultra 3D doesn't actually topple the Samsung SSD 850 Series on raw performance or warranty, the Ultra 3D is still a solid package and could conceivably give the Samsung SSD 850 EVO a run for its money. We're not awarding it an Editors' Choice award; it can't quite match the Samsung's drive performance, warranty, and software. But for most users it's not just more than sufficient, it's doggone good. (We did give WD's Blue 3D SSD an Editors' Choice award in the M.2 form factor, as the SATA competition is a little less stiff among M.2 SSDs in terms of breadth, and what comes in the box.)
The best part is if you like the Ultra 3D's numbers and vitals, but need it in an M.2 form factor, you can just get the WD Blue 3D M.2 version. WD and SanDisk have made a very solid family of drives with their 64-layer 3D NAND SSDs, so you won't go wrong with either brand if you jump into 3D TLC.
SanDisk's new 3D-NAND TLC-based drive is very competitive, reasonably priced, and all-around excellent. It's a safe alternative to the iconic SSD 850 EVO.
Like What You're Reading?
Sign up for Lab Report to get the latest reviews and top product advice delivered right to your inbox.
This newsletter may contain advertising, deals, or affiliate links. Subscribing to a newsletter indicates your consent to our Terms of Use and Privacy Policy. You may unsubscribe from the newsletters at any time.
Thanks for signing up!
Your subscription has been confirmed. Keep an eye on your inbox!
Sign up for other newsletters
