Lexar NM790 SSD review: excellent and affordable

In one look

Expert Rating

Benefits

• HMB 3.0 and dynamic SLC caching
• Low power consumption
• Good TBW

The inconvenients

• No 4TB option yet
• Lack of hardware encryption
• No heatsink option

Our opinion

The Lexar NM790 shows how far Gen 4 NVMe drives have come. It is affordable, offers excellent all-around performance, and offers exceptional energy conservation and good thermal control. All that’s missing is hardware encryption and a 4TB model.

The world of NAND storage is on the edge of uncharted territory, with capacities and performance likely to grow significantly in the near future.

With Gen 5 drives achieving high performance 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 business, prices are coming down and even budget drive performance is going up.

This is good news for the consumer, but is now the right time to invest in a PCIe Gen4 NVMe drive?

Design and build

• Simplified design
• No heatsink option

We talked about NVMe drive design and how the 2280 M.2 form factor has virtually eliminated the small variations that existed before.

Therefore, it should come as no surprise that the NM790 is a basic design with the NAND modules and controller on the top surface covered only by a thin sticker.

The underside has no visible components, suggesting that the NM790 was designed to be as simple as possible to manufacture and very reliable.

glossary

Without a heatsink, this design will fit easily into a laptop, PC or PlayStation 5 – but if you want to use it in the console, you’ll have to ignore Sony’s advice to stick with SSDs with a heatsink .

This is a drive you might be willing to take a chance on: as we’ll discuss later, this drive’s power consumption is considerably lower than some other Gen 4 NVMe drives, and so it doesn’t generate the same amount of heat.

Specifications and features

• 2TB storage caps
• No hardware encryption

Lexar only produces three sizes for the NM790, offering it in 512GB, 1TB, and 2TB models. The lack of a 4TB drive is a disappointment, and we’re hoping Lexar adds it and maybe a 8TB drive in the future.

To get the maximum performance from this drive, you must have an NVMe 2.0 M.2(2280) slot that supports PCIe Gen 4 x4 operations. It will work in a Gen 3 slot, but you won’t experience the performance levels seen in our testing.

Prior to this point, we recommend those with PCIe Gen 3 slots purchase drives designed for this interface, but with products like the NM790, these tips may need to be updated. Because a Gen 4 drive will still perform well, it has better potential if you upgrade your system, and Gen 3 drive prices aren’t noticeably lower.

glossary

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 RAM of the host system 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 user to the underlying speed of MLC NAND on the disks. . An added benefit for the disk manufacturer is that it avoids using expensive DRAM to do the caching, which also consumes extra power.

What Lexar doesn’t talk about is the controller on this drive, but a few other metrics like power consumption suggest it might not be a Phison E18 or derivative of that design, but of something created 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 how much module design has evolved over the past two years, as it uses nearly half the power of Lexar’s previous NM800PRO design with a 6W overhead, requiring only 3.5 W.

To compare this power consumption to other popular designs, the Samsung 990 Pro 2TB may require up to 5.8W, the Kioxia Exceria Pro up to 8.9W, and the Kingston KC3000 2TB requires an ominous 9.9W.

While the amount of voltage in all of these drives isn’t a concern for users of a mains-connected desktop system, for those with a laptop, the NM790 might be a perfect choice. Or, it would be if it had a feature that Lexar chose to leave out.

Mark Pickforward

From what we understand, this drive does not support hardware encryption. Although it is possible to use software to encrypt the contents of the NM790 using tools such as BitLocker, hardware encryption is the preferred method for those who want the highest level of security.

Security is one of the only areas where the NM790 may not be suitable for a specific ecosystem, but for the majority of users who choose not to encrypt everything, this is somewhat 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, manufacturers quote slightly different speeds within the capability range. The 512GB model is only rated for 7200MB/s sequential reads and up to 4400MB/s sequential writes. Where the 1TB and 2TB drives both offer the same 7400MB sequential read /s and the same sequential writes 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 efficient NVMe design.

The TBW of these drives scales with capacity, offering 500TB on the 512GB drive, 1000TB on the 1TB, and 1500TB on the 2TB. I’m not sure why the 2TB drive isn’t rated for 2000TB TBW, but 1500TB is a decent lifespan. To put that into perspective, writing the 50GB content from the Blu-ray drive to the 1TB drive every day should be possible for 20,000 days, or nearly 55 years. And, even if you write 1TB every day, the 2TB drive should last five years or more before the NAND runs out.

Using the 2TB drive as an example, the NM790 has a better TBW than the Samsung 990 Pro, nearly double that of the Kioxia Exceria Pro and only 100TB less than the Kingston KC3000.

In terms of performance, this drive is best viewed 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 performs much closer to high-end branded products, especially in “real world” tests.

Using CrystalDiskMark 8.04, the NM790 is very competitive for sequential reads and writes, good for random reads but bottom of the list for random writes. Using the Real World profile, the NM790 delivers one of the best sequential read performance we’ve seen, and write performance is acceptable.

Using ATTO Disk Benchmark, read speeds are at the higher end of the scale and write speeds are only slightly slower than high-end products. For many reasons, the PCMark10 Quick Storage benchmark likes the Samsung 990 Pro, but the NM790 scores higher than the Seagate FireCuda 530.

Our latest graph shows peak power consumption, which would be essential for battery-dependent laptop users. It wins this test by a country mile, using just 3.5W peak.

Overall the results are generally impressive, considering the cost of this module, and unless you need something with ridiculous IOPs or PCIe Gen 5, it’s a good choice and a great value price quality.

Pricing & Availability

Since there are plenty of Gen 4 drives that the NM790 is faster for, it would be reasonable to expect high prices, but this drive is incredibly cheap.

At the time of writing the UK price 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.

Pricing in the US should be “about the same” when the NM790 launches there in June.

These prices put the Lexar NVMe in direct competition with the Crucial P5 Plus, WD Black SN770, Seagate FireCuda 530 and Samsung 990 Pro.

Mark Pickforward

That’s a lot cheaper than the Samsung 990 Pro or the Seagate FireCuda 530, even though it performs pretty much the same in a desktop system. The WD Black SN770 is cheaper, but it only has a read speed of 5150MB/s.

The Crucial P5 Pro is priced almost the same as the NM790, but has slower read and write speeds and a lower TBW.

Check out our full ranking of the best SSDs for more options.

Verdict

The design and price of the NM790 puts Lexar firmly alongside Samsung, Crucial, Seagate and Kingston in delivering high performance NVMe modules with excellent specifications.

Where this drive is particularly desirable is the reduced power consumption, which makes 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. Beyond those two points, it’s a great choice for high-speed storage and should work just as well inside a PC or PS5.

Unless you want to try a lesser-known brand, in terms of value for money, the Lexar NM790 is a fantastic deal, and its specs make it the obvious choice for laptop upgrades.

Specifications

• Interface: NVMe 2.0 M.2(2280) PCIe Gen 4.0 x4
• Speed: 7400 MB/s read and 6500 MB/s write (on 1 TB and 2 TB)
• Abilities: 512 GB, 1 TB, 2 TB
• TBW: 500TB (512GB), 1000TB (1TB), 1500TB (2TB)
• Dimensions: 80 x 22 x 2.45mm
• Lester: 6g
• Operating temperature : 0-70C
• Maximum consumption: 3.5W
• Warranty/Support: 5-year limited warranty under TBW