Samsung 990 EVO Plus vs WD Black SN850X: Which One to Choose?

After the release of the Samsung 990 EVO Plus in late September of 2024, people are comparing it with many drives. The 990 EVO Plus is a flexible Gen 4.0 DRAM-Less SSD that can also use just two PCIe Gen 5.0 lanes. So, you can call it a hybrid Gen 5.0 NVMe as well. However, the WD Black SN850X is a full Gen 4.0 drive that was released in 2022.

Now, I am comparing these two because, if you look at their theoretical performance numbers, they are similar. There are minor differences in the companies’ claimed sequential and random read/write speeds. Although the 990 EVO Plus comes with much more advanced NAND flash and a controller, the SN850X has a long-standing reputation in the industry. I believe this comparison will be interesting, and by the end, you’ll be able to pick the right SSD for you.

The SN850X has a clear advantage in its own DRAM. But, because the 990 EVO Plus is modern, it comes with better components, such as a controller based on a 5nm process and a worth-mentioning V8 V-NAND. It will inherently generate and consume less heat than the SN850X at any time.

On the other hand, SN850X comes with a dedicated Game Mode 2.0 and a much bigger SLC Write cache. But the 990 EVO Plus has the NVMe 2.0 compared to the SN850X’s 1.4.

So, there are numerous advantages and disadvantages to both drives. But, if you are OK with a DRAM-less SSD, the 990 EVO Plus is surely a good pick in any case.

Note: DRAM-Less SSDs like the 990 EVO Plus use the system’s RAM via DMA (Direct Memory Access). It helps reduce prices, power consumption, and heat. There are some drawbacks that you can understand here.

Theoretical Specifications

Samsung’s V8 V-NAND is much denser, with more layers. But the 8TB variant with the SN850X is an advantage for capacity seekers.

The advertised sequential read/write numbers are almost matching, but in most places, the SN850X has a slight edge. In the random read/write IOPS, the 990 EVO Plus shows higher numbers, except for random read performance in the 1TB version.

The 990 EVO Plus is the smarter pick for users who want efficient PCIe 4.0 performance without overkill. Its DRAM-less design with HMB keeps it lean, cooler, and still blazing fast for daily workloads, gaming, and productivity. But suppose you hammer your drive with heavy multitasking, large file transfers, or content-creation workloads. In that case, the SN850X’s onboard DRAM and more aggressive firmware tuning give it a clear edge in sustained performance and latency stability.

Benchmark Scores Comparison

All the benchmark scores are for the 2TB variants of both drives. The game mode in SN850X is disabled.

PCMark 10 Full Drive Benchmark

PCMark 10 storage test puts the drive under real-world test environments. The tests include simulations of real-world tasks such as gaming, productivity, and content creation. You can choose between full and quick drive benchmarks, where the quick test runs only essential tests, such as file movement and application launching. The tests we are comparing are the Full drive benchmark tests for both. Three result metrics are compared, i.e., score, bandwidth, and latency.

In the PCMark 10 Full System Drive Benchmark, the Samsung 990 EVO Plus performs better overall. It scores 4,514 vs 3,850, giving it about a 17.2% advantage, and also delivers higher bandwidth at 719 MB/s vs 607 MB/s, roughly 18.5% higher. Latency favors Samsung as well, with 37 µs vs 43 µs, which counts to a 14% improvement. These gains suggest the 990 EVO Plus handles mixed workloads and multitasking more efficiently. Overall, the 990 EVO Plus is the stronger option for productivity and system responsiveness, while the SN850X remains a solid performer for gaming and everyday use.

3DMark Storage Test for Gamers

The 3DMark Storage test for gamers puts the drives under different gaming scenarios. The tests include simulating game installation, loading, saving, updating, streaming, and recording. A higher 3DMark score means better gaming performance from any drive.

In the 3DMark Storage Benchmark, the Samsung 990 EVO Plus holds a slight edge over the WD Black SN850X. Its overall score of 4,753 vs 4,466 shows about a 6.4% improvement, and bandwidth is also higher, i.e., 818 MB/s vs 761 MB/s, a 7.5% gain. Latency comes in marginally better, too, at 38 µs vs 40 µs, 5% lower. These small but consistent advantages suggest that the 990 EVO Plus is a bit quicker in high-load or mixed-workload scenarios. The 990 EVO Plus is therefore the better fit for productivity and multitasking workloads, while the SN850X still performs exceptionally well for gaming-focused systems.

CrystalDiskMark Sequential Benchmark Scores

CrystalDiskMark is a synthetic benchmarking software for computer storage devices. It gives us peak performance numbers and shows us where our drive can reach. We can choose different settings and preset profiles to suit different environments. We have selected a 1MB file size at queue depths of 8 and 1, respectively.

In the 1MB sequential tests, the 990 EVO Plus delivers slightly higher QD8 read performance at 7,153 MB/s vs. 6,982 MB/s, a 2.4% gain. However, the SN850X pulls ahead in QD8 write, hitting 6,676 MB/s vs. 5,917 MB/s, for a roughly 12.8% advantage. At lower queue depths, QD1 read favors the SN850X by about 22.8% (5,214 vs 4,246 MB/s), and QD1 write also goes to the SN850X, 5,982 vs 5,337 MB/s. Overall, the 990 EVO Plus excels in sustained read throughput, but the SN850X delivers better low-queue responsiveness and stronger write speeds.

CrystalDiskMark Random Benchmark Scores

For the random tests, the data blocks were 4K with queue depths of 1 and 256, respectively.

In the 4KB random tests, both drives perform closely, but each has its pros. The Samsung 990 EVO Plus edges out the SN850X in QD1 read, scoring 23,221 vs 22,853 IOPS with a modest 1.6% lead. For QD1, write, though, the SN850X wins with 91,200 IOPS vs 84,468, about 8% faster. At high queue depths, the 990 EVO Plus delivers 1,020,985 read IOPS, compared with 1,197,364 on the SN850X, which is about 17% slower. But it regains ground in QD256 write, where it hits 1,271,189 vs 1,175,695, roughly an 8.1% improvement. Overall, the SN850X handles heavy read workloads better, while the 990 EVO Plus shows stronger write scaling and slightly lower latency under sustained load.

Transfer Rate Benchmark

In transfer tests, performance varies across drives depending on the workload. The WD Black SN850 leads in copy transfer rate, scoring 1,827 MB/s vs. 1,541 MB/s, which is about an 18.6% advantage. The read transfer rate is nearly identical, with the 990 EVO Plus slightly ahead at 3,987 MB/s vs 3,936 MB/s, a negligible 1.3% edge. However, the 990 EVO Plus dominates write transfer, hitting 2,348 MB/s vs. 1,845 MB/s, a 27% improvement. Overall, the 990 EVO Plus excels in heavy write scenarios and file creation tasks, while the SN850 remains stronger for quick copy and mixed file operations.

Power Consumption and Efficiency

In terms of power efficiency, the Samsung 990 EVO Plus is clearly more optimized. It achieves 524 MB/s per watt compared to the SN850X’s 449, giving it roughly a 16.7% advantage in efficiency. The average power consumption is also lower, i.e., 3W vs 4W. The maximum draw is lower as well, 5W vs 7W, which helps reduce thermals during heavy use. Even the idle power is slightly better at 1,086 mW vs 1,124 mW, about a 3.4% difference. Overall, the 990 EVO Plus is the more power-efficient and thermally friendly drive, making it a better fit for laptops and compact builds.

TBW, DWPD, MTBF, and Warranty

If you want to know more about the TBW, MTBF, and DWPD, check out this article. The WD Black SN850X has a higher MTBF (Mean Time Between Failures), indicating better reliability. Everything else is the same in both.

Technical Specifications

Being a much more recent release, the Samsung 990 EVO Plus has the latest components, including the controller and NAND flash. It has the latest V8 V-NAND with 236 layers. When we look side by side, the SN850X looks outdated with the 112-layer BiCS5 TLC flash. The 5nm controller on the 990 EVO Plus contributes to lower power consumption, even during heavy read/write operations. The DRAM is undoubtedly an advantage here with the SN850X, but all other things are better with the 990 EVO Plus.

Thermals

The 990 EVO Plus runs much cooler than any of the popular Gen 4.0 drives. In most of the benchmarks, it idles at around 65°C. However, the SN850X is known for excessive heat, especially under heavy write loads. In fact, reaching 80 to 85°C under load is normal for this SSD. So, if you pick the SN850X and plan to put it under heavy load, itis best to opt for its heatsink version or use active cooling. With the 990 EVO Plus, there is generally no need of a heatsink.

Pricing

In terms of pricing, you will pay more for both the 1TB and 2TB variants of the SN850X than for the 990 EVO Plus. The 4TB variants are priced almost similarly.

By the time I am writing this article, the SN850X 1TB is available for 74.99$ while the 990 EVO Plus can be bought for 89.99$. The WD Black SN850X 2TB is priced at 146$ while the Samsung 990 EVO Plus is priced at 139.99$. The 4TB variant of the SN850X is available for 279.99$ while the 990 EVO Plus is priced at 269.99$. All in all, the 990 EVO Plus can be an economical option mainly because it is a DRAM-less SSD.

Which one to choose: WD Black SN850X or Samsung 990 EVO Plus?

In terms of raw performance, efficiency, and the latest tech, the Samsung 990 EVO Plus is clearly the right option. The absence of DRAM can be an issue for some people, but HMB technology has improved so much that the end user can hardly notice any difference in real-time performance. So, again, if you are OK with a DRAM-Less SSD, the 990 EVO Plus is perhaps the best DRAM-Less drive out there.

The WD Black SN850X has a higher capacity (8TB), better thermal management, dedicated DRAM, and a dedicated game mode. It has gained a good reputation for a long time. It is compared directly to the Samsung 990 Pro and 980 Pro. So, there is a trust factor here as well. Samsung has already given us the very popular DRAM-Less SSD, i.e., Samsung 980. So, in terms of brand reliability, there are no issues in any of them.

So, at the end of the day, if you are looking for the best performance at a lower price but are ready to compromise on DRAM and Game mode, you should go for the 990 EVO Plus. However, a DRAM SSD like the SN850X has advantages, such as better endurance and overall snappiness in real-world applications.

Price is another big factor here, and you can save enough while getting better performance with the 990 EVO Plus. So, if I have to choose between the both, I would go for the 990 EVO Plus.