Expert assessment
Advantages
- HMB 3.0 and dynamic SLC caching
- Lower power consumption
- Good TBW
cons
- There is no 4TB option yet
- Lacks hardware encryption
- No heat sink option
Our verdict
The Lexar NM790 shows how far Gen 4 NVMe drives have come. It is affordable, provides excellent all-round performance and features exceptional energy savings and good thermal control. The only thing missing is hardware encryption and a 4 TB model.
Price at review
American price TBC
The world of NAND storage is on the edge of uncharted territory, with capabilities and performance likely to grow significantly in the near future.
With Gen 5 drives being a performance priority but beyond the budget of many users, the Gen 4 drive market is about to heat up. And if the new Lexar NM790 is anything to go by, for those in the NAND storage sector, the prices are dropping and the performance of even budget drives is going up.
This is all good news for consumers, but is now the right time to invest in a PCIe Gen4 NVMe drive?
Design & build
- Simple design
- No heat sink option
We talked about NVMe drive design and how the 2280 M.2 form factor has largely eliminated the slight variations that existed before.
Therefore, it shouldn’t surprise anyone that the NM790 is a basic design with the NAND modules and controller on top, covered only by a thin sticker.
The underside has no visible components at all, indicating that the NM790 has been designed to be as simple as possible and very reliable.
Lexar
Without a heatsink, this design will easily fit into a laptop, PC or PlayStation 5 – but if you want to use it in console, you should ignore Sony’s advice to stick with SSDs with a heatsink.
However, this is one drive where you might be willing to take that chance: as we’ll discuss later, this drive’s power consumption is dramatically lower than some other Gen 4 NVMe drives, and therefore it doesn’t generate the same amount of heat.
Specifications and Features
- Caps on 2TB storage
- No hardware encryption
Lexar only produces three sizes for the NM790 and offers them in 512GB, 1TB, and 2TB models. The lack of a 4TB drive is a disappointment, and we hope Lexar adds this and maybe an 8TB drive in the future.
To get the maximum performance out of this drive, an NVMe 2.0 M.2(2280) slot that supports PCIe Gen 4 x4 operations is required. It will work in a Gen 3 slot, but you won’t experience the levels of performance you’ll see in our tests.
Prior to this point, we recommend those with a PCIe Gen 3 slot to buy drives designed for that interface, but with products like the NM790, that advice may need updating. Because a Gen 4 drive still performs well, it has better potential if you upgrade your system, and Gen 3 drive prices aren’t substantially lower.
Lexar
Overall, what this drive has better than older designs is that it supports HMB 3.0 and Dynamic SLC Caching, allowing it to achieve and maintain high levels of performance using the host system’s RAM and the ability to dynamically convert NAND to cache memory.
For those with lots of RAM and plenty of free disk space, it is possible to maintain write speeds for large files without exposing the underlying speed of the MLC NAND on the disks to the user. An added bonus for the disc maker is that this avoids using expensive DRAM to perform the caching, which also consumes additional power.
What Lexar doesn’t discuss is the controller on this drive, but a few other indicators like power consumption suggest it might not be a Phison E18 or a derivative of that design, but something made in-house.
When we first encountered Gen 4 drives, the performance they offered was impressive, but power consumption and, by extension, heat generation was often an issue.
The NM790 shows just how far module design has come in recent years, as it uses nearly half the power of Lexar’s previous NM800PRO design with an overhead of 6W and requires only 3.5W.
To compare that power consumption to other popular designs, the Samsung 990 Pro 2TB can demand up to 5.8W, the Kioxia Exceria Pro needs up to 8.9W, and the Kingston KC3000 2TB wants an alarming 9.9W.
While the amount of strain in all of these drives isn’t something users with a mains-connected desktop system would be concerned about, the NM790 could be a perfect choice for those with a laptop. Or it would be if it had a feature that Lexar chose to leave out.
Highlight Pickavance
As far as we understand, this drive does not support hardware encryption. While it is possible to use software to encrypt the contents of the NM790 with tools such as BitLocker, hardware encryption is the method of choice for those who want the highest level of security.
Security is one of the few areas where the NM790 may not be suitable for a specific ecosystem, but for the majority of users who choose not to encrypt everything, it’s something of a non-issue.
Performance
- Up to 7400 MB/s sequential read
- Up to 6500 MB/s sequential write
- Great longevity
As with many NVMe designs, the makers quote slightly different speeds across the capacity range. The 512 GB model is only capable of sequential read speeds of 7200 MB/s and sequential write speeds of up to 4400 MB/s. Where the 1 TB and 2 TB drives both offer the same sequential read speeds at 7400 MB/s and sequential write speeds at 6500 MB/s.
For this reason and the relatively low price of the 1TB drive, we’d avoid the 512GB option.
All of our testing was done on the 2TB drive and it lived up to its billing as a very modern and effective NVMe design.
The TBW of these drives scales with capacity, offering 500 TB on the 512 GB drive, 1000 TB on the 1 TB, and 1500 TB on the 2 TB. I’m not sure why the 2 TB drive isn’t rated for 2000 TB TBW, but 1500 TB is a decent longevity. To put that in perspective, writing the 50 GB of content from the Blu-ray drive to the 1 TB drive each day should be possible for 20,000 days or nearly 55 years. And even if you write 1 TB every day, the 2 TB drive should last five years or more before the NAND is exhausted.
Using the 2 TB drive as an example, the NM790 has a better TBW than the Samsung 990 Pro, almost double that of the Kioxia Exceria Pro, and only 100 TB less than the Kingston KC3000.
In terms of performance, it’s best to think of this drive in the context of budget drives like the Crucial P5 Plus and WD Black SN770, as it costs about the same. However, in some benchmarks, this drive far outperforms premium branded products, especially in “real world” tests.
With CrystalDiskMark 8.04, the NM790 is very competitive for sequential reads and writes, good at random reads, but is at the bottom of the list for random writes. Using the Real World profile, the NM790 delivers some of the best sequential read performance we’ve seen, and the write performance is acceptable.
Using the ATTO Disk Benchmark, the read speeds are at the high end of the scale and the write speed is only marginally lower than the premium products. For several reasons, the PCMark10 Quick Storage benchmark loves the Samsung 990 Pro, but the NM790 scores higher than the Seagate FireCuda 530.
Our final chart shows maximum power consumption, something that would be critical for laptop users who rely on battery power. It wins this test by a country mile, using just 3.5W at peak times.
Overall, the results are generally impressive given the cost of this module, and unless you need something with ridiculous IOPs or PCIe Gen 5, this is a good choice and great value for money.
Price & availability
Given that there are many Gen 4 drives out there that make the NM790 faster, it would be fair to expect premium pricing, but this drive is shockingly cheap.
At the time of writing, UK pricing is on Amazon for the 512GB version is £44.00, the 1TB model is £64.99 and the 2TB is just £119.99, with similar options on eBuyer.
Prices are expected to be “roughly the same” in the US when the NM790 launches there in June.
Those prices put the Lexar NVMe in direct competition with the Crucial P5 Plus, WD Black SN770, Seagate FireCuda 530, and Samsung 990 Pro.
Highlight Pickavance
It’s much cheaper than the Samsung 990 Pro or Seagate FireCuda 530, even though it performs pretty much the same in a desktop system. The WD Black SN770 is cheaper, but only has a read speed of 5150 MB/s.
The Crucial P5 Pro is almost the same price as the NM790, but has lower read/write speeds and a lower TBW.
Check out our full ranking of the best SSDs for more options.
Pronunciation
The design and price of the NM790 put Lexar firmly alongside Samsung, Crucial, Seagate, and Kingston for offering powerful NVMe modules with excellent specs.
Where this drive is especially desirable is its reduced power consumption, making it a no-brainer for laptop upgrades.
There are only two disappointments: the first is the lack of hardware encryption; and the second is the lack of a 4TB model at launch. Those two points aside, this is a great choice for fast storage and should work equally well on a PC or a PS5.
Unless you’re willing to try a lesser-known brand, the Lexar NM790 is a fantastic deal value-for-money, and its specs make it the obvious choice for laptop upgrades.
Specifications
- Couple: NVMe 2.0 M.2(2280) PCIe Gen 4.0 x4
- Speed: 7400 MB/s read and 6500 MB/s write (on 1TB and 2TB)
- abilities: 512GB, 1TB, 2TB
- TBW: 500TB (512GB), 1000TB (1TB), 1500TB (2TB)
- Dimensions: 80 x 22 x 2.45mm
- Weight: 6 gr
- Operating Temperature: 0-70C
- Maximum power consumption: 3.5W
- Warranty/Support: limited 5-year warranty under the TBW