Micron 9400 Pro and Max: Capacities, TBW, Power, Part-Number Codes and UK Prices

Micron 9400 Pro vs Micron 9400 Max: two models, two lists

Micron's 9400 technical product specification, Rev. B of April 2025, covers two models with different capacities and separate tables throughout. Before you use any figure, check which model it belongs to. In the grid below, each cell runs in that model's capacity order, smallest first.

The sequential and random read rows are identical, so a read-heavy comparison will not separate the two. The split shows up in random write, mixed workloads and endurance. The specification's headline of up to 600,000 IOPS random write belongs to MAX: the PRO table reads 300 KIOPS. A title that pairs PRO with 600,000 IOPS is mixing the two.

Micron measures at steady state as defined by SNIA's enterprise test specification, with drive write cache enabled, at queue depths of 32 for sequential, 256 for random read and 128 for random write, on a generic X570 board with an AMD Ryzen 7 3700X. It says numbers vary with the host system.

Micron 9400 SSD endurance: TBW, and what DWPD works out to

The specification states endurance as total bytes written, and we have not found a Micron document stating a DWPD figure for the 9400. Micron calls the TBW values the theoretical maximum endurance for the given transfer size and type, adds that actual lifetime varies by workload, and points to Percentage Used in the SMART/Health log to check the device life used.

Our arithmetic, not Micron's. Each PRO 4K random TBW divided by its capacity gives 1,825 full-drive writes: 14,016 TB over 7.68 TB, 28,032 TB over 15.36 TB and 56,064 TB over 30.72 TB. Spread over 5 years of 365 days, that is 1 drive write per day (DWPD). Each MAX figure gives 5,475, which is 3 DWPD on the same sum. The 5 years is our assumption for the sum. Micron's general data centre SSD warranty, set out further down, also runs five years from shipment, but we found no document tying it to the 9400 by name.

On that same spread, a 30.72TB PRO takes about 30.72 TB a day and a 25.6TB MAX about 76.8 TB a day, so the smaller MAX absorbs more writes than the larger PRO. We use the 4K random rows for this because they are the lower of Micron's two: the 7.68TB PRO reads 14,016 TB on 4K random and 58,300 TB on 128K sequential.

Micron 9400 Pro 32TB, 30.72TB, 15.36 TB and 7.68 TB: reading the label

Micron's capacity list has no 32TB model. The PRO list stops at 30,720GB, and 32TB appears only in the specification's figure captions, as a 16TB/32TB capacity point beside a separate 8TB one. Those captions are not split by PRO and MAX. So a title reading Micron 9400 Pro 32TB most likely means 30.72TB, on our reading, and the part number is how to confirm it.

Within the PRO line the three sizes differ less than the labels suggest. The 7.68 TB and 15.36 TB rows match on sequential speed, random read and random write, and differ by 10 KIOPS on the mixed workload. The 30.72TB gives up 100 KIOPS of random read. Active read rises with size, 17 W, 18 W and 21 W.

Micron 9400 part numbers: how to read the code

The specification prints a part-number chart, says not all options can be combined to define an offered product, and points to micron.com for a list of valid part numbers. We have not found a Micron document listing complete 9400 part numbers, so this page works from the chart's segments.

The other labelled segments are MT for Micron Technology, K for PCIe Gen4, CC for U.3/U.2 (2.5 inch, 15mm, SFF-8639), GH for 9400 PRO and GJ for 9400 MAX. Note the trap in code 12TB: it means 12,800GB, not 12 TB. Read on this chart, MTFDKCC30T7TGH is a PCIe Gen4, U.3/U.2, 30,720GB 9400 PRO. We assembled that string from the chart's segments, and we have not seen it on a Micron list.

Micron's warning is a live one. The chart's own sample reads MT FD K CC 6T4 T GH, which sets a capacity code from the MAX list beside the PRO family code. The chart, as we read it, does not label FD, the T before the family code, or the trailing 1 BC 4, so we do not guess at them.

Micron 9400 NVMe SSD power: 5 W idle, up to 25 W active

Each cell runs in that model's capacity order, smallest first.

Two sets of cells look odd and we print them as Micron does. On 128K sequential write, the 15,360GB PRO draws 20 W, more than the 30,720GB PRO at 17 W, and the 12,800GB MAX draws 13 W, less than the 6,400GB MAX at 15 W. The MAX sequential read row also peaks at its middle size, 16 W. The revision history describes Rev. B as a typo correction and we have not found a later one, so do not size a power budget on these rows alone.

Idle is flat at 5 W, so it weighs less per terabyte on a bigger drive: on our arithmetic about 0.65 W per TB at 7.68TB and about 0.16 W per TB at 30.72TB. That is a paper figure and leaves out load and cooling. The supply rails are 12 V within 8% and 3.3 V auxiliary within 5%, with a typical peak inrush of 2.0 A on the 12 V rail.

Micron 9400 power-loss protection, reliability and warranty

• Power loss: the specification lists full power-loss protection.
• Data integrity: end-to-end data protection, and static and dynamic wear levelling.
• MTTF: 2 million device hours, which Micron says rests on population statistics not relevant to individual units.
• Uncorrectable bit error rate: under 1 sector per 10^17 bits read.
• Operating temperature: 0°C to +70°C, measured by SMART.
• Hot-plug: surprise insertion and removal, and hot-plug capable.
• Firmware: digitally signed and field upgradeable.
• Sector size: 512 and 4096-byte, configurable. Namespaces supported: 128.

Micron's specification gives power-loss protection that one list line and no explanation of how it works. For how one maker describes the mechanism, the Samsung PM9A3 page prints Samsung's wording, which is about a different drive.

On warranty, the specification's first page says to contact your Micron sales representative for additional technical and warranty information. Separately, Micron publishes a general Data Center SSD Limited Warranty, revised 24 July 2020. It says any claim must be made within five years from the date of shipment by Micron, or before the SSD exceeds its specified useful life, whichever is earlier. It is Micron's general data centre SSD warranty: it does not name the 9400, and we found no document tying it to the 9400 by name.

Micron 9400 and the UKCA line for UK buyers

Micron's compliance list carries a line for this market: 'UKCA (UK): SI 2016/1091 Class A and SI 2012/3032 RoHS', alongside a separate CE line for Europe. It is the one line in this specification that names the UK. It is Micron's statement about the product. We have not seen a certificate for any unit.

The same document carries a limit that matters when buying through a marketplace. Micron says you may not rely on information in it if you obtain the product from an unauthorised distributor or other source Micron has not authorised. Its general warranty likewise says the product must have been purchased from Micron or a Micron authorised distributor. We have not found a document stating which Amazon.co.uk sellers, if any, Micron authorises, so ask the seller directly if this matters to your purchase.

Micron 9400 form factor: U.3/U.2, 15 mm, single port

There is one form factor across both models: a 2.5-inch U.3/U.2 drive with an SFF-8639 connection, 100.45 x 70.10 x 15.00 mm and under 235 g. It runs PCIe Gen4 under NVM Express 1.4, and the specification gives it as single port, x4. SNIA's 2022 slides describe the 2.5-inch device evolving into PCI Express U.2.

Quarch Technology, in a 2019 article, describes U.3 as a tri-mode standard that builds on the U.2 specification and uses the same SFF-8639 connector. It says U.3 drives are backward compatible with U.2, and that U.2 drives are not compatible with U.3 hosts. That is a general statement about the two standards, not a Micron one. The U.3 SSD page goes further into the standard.

Two checks follow. The drive is 15 mm thick, so your bay has to accept that height. And it is single port, so a system built around two paths to one drive needs a dual-port model instead. We have not found a Micron document explaining how a U.3/U.2 drive behaves on each type of backplane, and we hold no list of servers, so settle both from your server's own documents.

Micron 9400 Pro price on Amazon.co.uk

When the table holds rows, "Prices checked" at the top of the page gives the time of reading. Prices are pounds sterling inc VAT, sorted per TB, and each row shows its condition. The table holds 1 listing right now. That includes 1 listing in new condition. PRO and MAX can sit in one table, so check the family code before comparing rows.

Titles are the seller's wording, and a part number decides what a row is. Look for GH or GJ and the capacity code from the chart above, and if a listing gives no part number, ask for it before you press Buy on Amazon. For the choice of interface before the model, enterprise SSD covers SATA, SAS and NVMe.

In-stock alternatives

None of these is the product this page covers: they are what is in stock on Amazon.co.uk beside it right now. Each row says why it is listed. Check the interface, form factor and part number against your system before buying.