The Samsung 990 Evo Plus: perfect for notebooks

Samsung SSDs dominate the sales charts in our online shop, with the bestseller being the 990 Pro. And now the new 990 Evo Plus is preparing to topple its older sibling from the throne. It doesn’t manage to outstrip the Pro in terms of performance, but at it’s still cheaper.

Features and specs

Samsung uses the Piccolo controller with four memory channels for the 990 Evo Plus. You have to forgo your own DRAM cache. Generally speaking, SSDs with DRAM chips offer better performance than those without.

By using the NVMe function Host Memory Buffer (HBM), this at least minimises such a drawback. HBM uses part of the host computer’s working memory as cache storage, although it’s not quite as fast as a DRAM cache. The SSD is connected via PCIe 4.0.

The sequential read rate should be 7,250 MB per second (MB/s). In terms of sequential write rate, it achieves 6,300 MB/s, putting it 200 or 600 MB/s behind its older sibling.

When it comes to NAND memory, Samsung uses its own new V8 with 236 layers. This is a TLC with 3 bits per memory cell. NAND is a non-volatile memory technology that doesn’t require power to store data. The new interface should be twice as fast as the memory on the 990 Evo (without the «Plus» in its name).

My two-terabyte (TB) model for this review boasts four NAND memory modules. The SSD’s warranty lasts five years or up to a set write limit. This varies depending on the storage capacity. In my case, it’s 1,200 TB of written data, which is pretty generous of Samsung. To achieve this amount of data in five years, you’d have to write 657 GB of data every day.

Reading: weak when it comes to random read

I measure read speed with the CrystalDiskMark program. This shows that the Samsung 990 Evo Plus doesn’t achieve its promised speed. But this is often the case because manufacturers test under lab conditions while I’m putting it through its paces in my home office. The 990 Pro doesn’t reach the promised 7,450 MB/s either.

The first value per SSD in the graph refers to sequential reading. Meanwhile, the second value relates to random reading and writing. If you work with large files, the first is relevant to you, and if you deal with small files, you’ll want to look at the second.

While the differences in sequential reading are small, the 990 Evo Plus shows weaknesses in random reading and gets left behind by the competition.

Writing: only a bigger difference in theory

The differences compared to the other SSDs are greater when writing. However, you can already see this from the data sheet. Nevertheless, the 990 Evo Plus is still disappointing, being 550 MB/s behind the promised write speed of 6,300 MB/s .

In a practical test, I copy a 10 GB file from a RAM disk to the SSD. The RAM disk ensures the SSD’s the bottleneck, as the disk achieves a much higher read and write rate. This is where Samsung’s SSD performs well. It can even outperform some competitor models.

To test how the SSD behaves when writing data continuously, I repeatedly write the 10 GB test file from the RAM disk to the SSD using a batch command. This allows me to determine when it starts to throttle down. After 216 GB of written data – the end of the SLC cache – the speed drops from 4,400 MB/s to 1,200 MB/s on average. That’s a respectable performance.

If the SSD is 80% full and I repeat the test, I can also achieve maximum speed for 216 GB of written data. After that, it drops to around 1,200 MB/s.

Copying: the 990 Evo Plus can’t keep up

When copying, in other words reading and writing to the SSD at the same time, I duplicate the 10 GB file on the drive. In this scenario, the Evo 990 Plus clearly lags behind competitor SSDs. It drops even more at 80% full.

Gaming: good performance

The 990 Evo Plus performs better than its older sibling in the 3DMark gaming benchmark. Compared to the other SSDs, it achieves similar values. At 80% full, it hardly loses any performance.

Office: achieves good values

In office-based applications, the 990 Evo Plus is far ahead. Even at 80 per cent full, it performs admirably in this test.

Power consumption and temperature:cool and efficient

The 990 Evo Plus is frugal and only needs slightly over 5 W, even under full load. This low power consumption is also reflected in the temperature, where I measured a maximum of 68°C. Other models, such as its bigger sibling, easily get ten degrees hotter.