WD Black SN770M SSD review: A great but overkill 2230 SSD

2230 SSDs are hot right now since they're the only SSDs that can fit inside handheld gaming PCs, and when it comes to high-end handhelds like the ROG Ally, people want high-end SSDs. To fulfill that demand, Western Digital has launched its first premium 2230-sized drive, the WD Black SN770M. Today, it's the fastest 2230 SSD you can buy, but its incredible speed is a fair bit overkill for the task of gaming. It can however find a great home in the higher-end gaming handhelds and also laptops that use the 2230 form factor, like the Microsoft Surface Pro.

About this review: Western Digital sent us the WD Black SN770M 2TB for the purposes of this review. Western Digital did not see the contents of this review before publishing.

WD Black SN770M: Pricing and availability

At the time of writing, the SN770M has just launched, and so far two models are available: the 1TB for $110 and the 2TB for $220. The SN770M has the best availability on Best Buy thus far, but there are listings on Amazon that should hopefully see better supply in the coming months. Both the relatively high price and low availability for such a niche product isn't unexpected at launch.

Compared to other 2230 SSDs, the SN770M is definitely the most expensive. The 1TB versions of Corsair's MP600 Mini and Sabrent's Rocket 2230 are both $90 at the time of writing, and Teamgroup's MP44S 1TB is almost half the price at $70. Western Digital clearly feels that a bit of a premium is justified for the WD Black SN770M, and the company might not be wrong.

How the WD Black SN770M was tested

I tested my SN770M 2TB in a test system comprised of Asus's TUF Gaming B650-Plus motherboard, AMD's Ryzen 7 7800X3D CPU, and 16GB of DDR5 rated at 5,600MHz and CL40. However, it's important to keep in mind that the Steam Deck, unlike my test bench, runs at PCIe 3.0 rather than PCIe 4.0, which will limit the performance of any 2230 SSD that's rated for PCIe 4.0 like the SN770M, and this is a key reason why I'm testing using this PC rather than my Steam Deck. Higher-end devices like the ROG Ally won't have this problem since they run at PCIe 4.0.

I ran the SN770M through three benchmarks that show a mix of real world and synthetic performance metrics: CrystalDiskMark, an app that shows theoretical maximum performance in a variety of tests; 3DMark's storage benchmark, which is a compilation of real world tests wrapped up in one seamless benchmark; and IOMeter, a synthetic benchmark that I use to show how fast SSDs will be in a continuous writing scenario. To prevent cache depletion from impacting results, I waited 10 to 15 minutes between each test so that the cache could refill properly.

For comparison, I've included test results from Teamgroup's MP44S and Sabrent's Rocket 2230. Both of these drives have better bang for buck when it comes to capacity, especially the MP44S (though the gap might close over time). The Rocket 2230 was arguably the SSD that started this trend and has reigned as the fastest 2230-sized drive ever since it launched nearly a year ago.

Performance

CrystalDiskMark includes six preconfigured tests, which is what I ran on all the SSDs. These tests vary in sequential vs random, block size, queue depth, and thread count, offering a wide variety of metrics to analyze.

Scores are organized by read/write and are measured in MB/s.

It's nearly a total blowout for the SN770M, which was the fastest or tied as the fastest in five of the six tests. Its sequential performance in particular was much better than either the MP44S's or the Rocket 2230's, while random performance was mostly good but faltered in the 32 queue depth, 16 thread test. Still, that random test where the SN770M lost is fairly niche and not quite as important as the wins in the other two random tests, which have proven to be some of the hardest tests for SSDs to improve in.

Western Digital clearly feels that a bit of a premium is justified for the WD Black SN770M, and the company might not be wrong.

The storage test in 3DMark tests loading times in three AAA games, how long it takes to install and move games, how quick saving is, and how smooth game recording is. It's a controlled yet mostly realistic benchmark.

While the SN770M is clearly in first place here, it's not by much. It's 14% better than the MP44S and just 7% better than the Rocket 2230. These kinds of margins don't exactly make for a game-changing experience on the SN770M unfortunately.

IOMeter is a piece of software developed by Intel in the 1990s, yet it's still the best way to show how well an SSD performs if it's been writing large files over a large period of time. SSD performance tends to decline over the course of a large file transfer, as an SSD's high-speed cache is depleted and the SSD eventually has to rely on its normal storage, which is slower, sometimes vastly slower. I had IOMeter consume 50% of each drive's capacity and then wrote data in 1MB blocks at a queue depth of 8 for 15 minutes continuously.

Scores are measured in MB/s.

The SN770M exhibited some interesting behavior in IOMeter, peaking at nearly 4,400MB/s and staying there for a minute. As the test went on, its performance alternated between 1,000MB/s and roughly 4,300MB/s. Meanwhile, the Rocket 2230 started at a speed of 4,600MB/s and within seconds it dropped to about 1,800MB/s where it hovered for the remainder of the test. The MP44S by contrast didn't even make it a minute before its performance totally plummeted to 100MB/s. On average, the SN770M was clearly the faster drive here, even compared to the Rocket 2230.

It's nearly a total blowout for the SN770M.

The SN770M's performance advantage will make a big difference if you're transferring files over a long period of time, as the SN770M is about 25% faster than the Rocket 2230 and a whopping 6.7 times faster than the MP44S. However, at least for the Steam Deck and ROG Ally, it's hard to imagine anyone doing too much if this considering each handheld (and every other handheld to my knowledge) can support only one SSD.

Should you buy the WD Black SN770M?

You should buy the WD Black SN770M if:

• You want the fastest 2230 SSD possible
• You want a high-capacity 2230 SSD for your Steam Deck, ROG Ally, Surface Pro, or other device

You shouldn't buy the WD Black SN770M if:

• You don't want the most expensive 2230 SSD
• You know you won't get much out of the SN770M's impressive but niche writing performance

Obviously, the WD Black SN770M is a great 2230 SSD, but I do have some qualms about its high price tag. Since it's a new addition to the market, however, I expect it to decline sooner or later. With a lower price tag, it'll be very easy to justify spending a little extra for the best 2230 SSD. The MP600 Mini or Rocket 2230 are now in a really awkward position, having been the best 2230 SSDs but now are in the midrange, squeezed by the cheap MP44S at the bottom and the SN770M from the top.

The SN770M's performance advantage will make a big difference if you're transferring files over a long period of time, as the SN770M is about 25% faster than the Rocket 2230 and a whopping 6.7 times faster than the MP44S.

I still think the Rocket 2230 and MP600 Mini are worth buying since shaving off around $20 per terabyte is pretty decent, but that's just a drop in the bucket to users who bought the ROG Ally, which is a great fit for the SN770M. Another device you might want to put the SN770M in is the Surface Pro, or any similar laptop that uses 2230 SSDs. If you own a Steam Deck, however, I'd recommend against the SN770M since it would be limited by PCIe 3.0 speeds, which makes the MP44S and its much better value significantly more attractive.