The available M.2 SSD form factors have been pretty constant over the past years. Basically everything uses the M.2 2280 format, which makes the drives 22 mm wide and 80 mm long. No doubt, these dimensions are great for desktops and most laptops. With the release of the Steam Deck and ROG Ally portable game consoles, this status quo has changed. An 80 mm SSD is suddenly pretty big, considering the whole Steam Deck is just 30 cm long and 12 cm wide. That's why these new consoles use drives built on the smaller M.2 2230 form factor—just 3 cm long.

When buying a Steam Deck from Valve you can choose between a 256 GB SSD ($400) and a 512 GB model ($380). Recently, the company announced their new OLED Steam Decks, which come at a price of $550 for the 512 GB OLED model, and $650 for the 1 TB version. There's also a 64 GB eMMC option for $296, which can be upgraded with an NVMe drive (all hardware versions have an M.2 slot). It looks like with the release of the OLED design, there will be no more eMMC version. Still, it could be a cost-effective approach to get a Steam Deck without spending too much, but you'll need to find a decent M.2 2230 SSD to achieve better storage speeds.

Until now there were basically three kinds of M.2 2230 drives: the WD Black SN770M using a WD controller, various Phison E21 with QLC NAND based drives (PNY CS2142, Addlink S91, Team Group MP44S, Corsair MP600 Core Mini), and the Corsair MP600 Mini, which uses TLC NAND with a Phison E21 controller, too. Now the Corsair MP600 Mini 2 TB is available, and it uses a new controller and flash combination: Phison E27 with 162-layer Toshiba TLC NAND flash. This is the same platform that we saw on the full-size Corsair MP600 Elite. There's a small difference though, the MP600 Elite uses two NAND chips, whereas the MP600 Mini in today's review uses only one. This makes it harder for the controller to spread data around and also affects the transfer rates between controller and NAND, especially when the SLC cache is full.

Given the limited physical space available, a DRAM cache is not included—same as on all other M.2 2230 drives. Higher-end drives have a separate DRAM cache chip that stores a copy of the mapping tables of the SSD. This table helps the controller figure out where a piece of data is located; like most DRAM-less SSDs, the MP600 Mini does use some of the host system's memory, though (HMB or Host-Memory-Buffer). The HMB size is 64 MB.

Synthetic performance results of the Corsair MP600 Mini are very impressive, especially for such a compact drive. In random IO they are actually topping our charts. Phison has a long history of optimizing their controllers for typical synthetic reviewer workloads on an empty drive, but still that's some nice gains. I really like the high mixed IO results, because during typical usage you'll never just have reads, or just writes. Actual usage patterns are always a mix of read and write operations, that's why mixed IO performance matters a lot. Our real-life testing runs actual games and applications, it does not replay disk traces, which means time spent on the CPU is realistically factored into the performance results. We also test with the drive filled to 85% of its capacity. This approach puts additional pressure on the various algorithms and the SLC cache, just like in real-life.

In these tests the MP600 Mini does very well, and is able to beat or match famous drives like the Samsung 980 and 980 Pro, and Hynix Gold P31. It's also really close to the WD SN850, Solidigm P44 Pro and Kingston KC3000—all of those are full-size eight-channel designs. Compared to other M.2 2230 drives the new MP600 Mini is much faster, too. Especially the QLC models fall much behind. Even compared to the MP600 Mini 1 TB the performance uplift is 16% and the WD Black SN770M offers roughly the same speed as the MP600 Mini 2 TB. This makes the MP600 Mini 2 TB a fantastic choice for gamers using a Steam Deck or other portable gaming console. An interesting academic comparison is MP600 Elite vs MP600 Mini, because the only difference is that the former has two flash chips whereas the latter has a single one, due to the limited space. Depending on the benchmark this lack of additional parallelism turns into a few percent lower performance, but nothing serious.

Corsair's drive comes with an SLC cache size of just 49 GB, which is tiny by today's standards, especially on a 2 TB drive. No idea why Corsair picked such a small size. This is the same setting as on the MP600 Elite, so it looks like either nobody cared to look into it, or they decided to stick with the small SLC cache. While 49 GB is still plenty for nearly all workloads, it's still smaller than virtually all competing drives. Do consider that your Steam Deck's game installation performance will be limited by your internet speed, so even 700 MB/s worst-case will still be plenty. Filling the whole 2 TB capacity completed at 770 MB/s, which is a very good result for an M.2 2230 SSD—better than all other competitors, except for the MP600 Mini 1 TB, which reached 1315 MB/s in the same test. Just to put things into perspective, the various QLC drives manage only 120-140 MB/s in this test, and the WD SN770M, while slightly faster in real-life testing, achieves just 442 MB/s here.

Our power consumption tests show that the Phison E27T is a highly energy-efficient design. It is able to successfully enter the lowest-power L1 ASPM power state, which is important for mobile devices, to not drain the battery when idle. Energy efficiency during ready and writes is near the top of our charts, the WD SN770M is still a bit more efficient during reads, but less efficient in writes. Considering the usage patterns of the Steam Deck, I'd say that's a small win for the WD drive, because portable consoles will read more often than write.

Thermal performance of the MP600 Mini is not that great, despite the good energy efficiency. It looks like Corsair was ultra cautious with the drive's thermal limits, and it will start throttling at just 80°C—had they allowed something higher like 90°C or 95°C it would have been much easier to avoid throttling. When installed in a Steam Deck, thermals should be fine, because the drive isn't loaded nearly as much as in our thermal stress test.

Priced at $230 for the tested 2 TB model, the MP600 Mini is not cheap. The strongest competitor is the WD Black SN770M, which sells for just $180 right now, heavily discounted from its MSRP of $220—with slightly higher overall performance, better read energy efficiency, but only half the sustained write performance. Still, given the $50 price difference I'd pick the SN770M. At similar pricing, either drive will be an amazing choice for maximizing storage performance of the portable consoles. If you don't need the highest performance, then the various QLC offerings let you save quite some money—Silicon Power UD90 2 TB sells for just for $140, Team Group MP44S is $150. That's pretty much it for 2 TB M.2 2230 options. There's the Corsair MP600 Mini 1 TB for $90—but that's too small for many. Also, considering the older controller I'd rather grab the newer 2 TB version for the substantially improved performance. Corsair has confirmed that the older MP600 Mini 1 TB will see a refresh in the coming weeks, to receive the same hardware configuration as the MP600 Mini 2 TB (Phison E27 + Toshiba TLC NAND).