Samsung Portable SSD P9 Reaches 4,048 MB/s While iPhone Owners Weigh 10Gbps Magnetic Cases
In StorageReview’s lab tests, the Samsung Portable SSD P9 achieved sequential reads of 4,048 MB/s and writes of 3,769 MB/s, though that same testing revealed the drive falling to a 540 MB/s plateau during extended writes. Retailing at $649.99 for the 2TB model, the drive packs desktop-class speed that an iPhone shooting ProRes video cannot fully utilize. Spanning the iPhone 17 and iPhone Air up to the iPhone 18 Pro and iPhone 18 Pro Max, Apple’s November 2026 runs lineup uses USB-C connections exclusively to interface with external storage devices.
StorageReview tested the P9 alongside competing hardware using a Thunderbolt 5 laptop running fio. Tom’s Hardware evaluated the drive with CrystalDiskMark 8, PCMark 10, DiskBench, and Iometer on a Ryzen 7600X desktop equipped with native USB4.
Sealed USB4 Performance Versus Magnetic Phone Storage
Three primary hardware routes exist for adding external storage to a modern iPhone. Sealed USB4 drives like the Samsung P9, SanDisk Extreme PRO USB4, and LaCie Rugged SSD4 offer factory-assembled enclosures, warranties, and ratings between 3,700 and 4,000 MB/s. However, their metal shells lack magnetic arrays, leaving them to dangle from cables during mobile shoots. Prices for sealed drives reflect tightening NAND flash supplies driven by AI demand and constrained manufacturing, with Mezha reporting contract prices tripling over a year.
Magnetic M.2 enclosures from manufacturers such as UGREEN and ORICO clamp directly onto MagSafe-compatible phones using a 10Gbps USB 3.2 Gen 2 link. These enclosures ship empty, requiring users to supply a separate 2230 or 2242 NVMe module. Prebuilt magnetic options like the Lexar ES5 Magnetic and SanDisk Creator Phone SSD eliminate assembly steps. StorageReview tested a 2TB unit of the Lexar ES5, while separate retail checks tracked the SanDisk Creator Phone SSD near $224.99 for a 1TB capacity.
Storage enclosure temperatures spike during mobile recording sessions
Workloads on a mobile phone differ entirely from desktop synthetic benchmarks. Thermal management separates the hardware options during extended recording sessions. StorageReview logged a peak temperature of 40C for the P9, whereas the SanDisk Extreme PRO reached 62C, the LaCie hit 60C, and the Lexar ES5 reached 70C.
DIY USB4 and 80Gbps enclosures from brands including Satechi, OWC, TerraMaster, HyperDrive, ULANZI, and others offer an alternative upgrade path for users splitting workflow between a phone and a laptop. Satechi incorporates active cooling into its 40Gbps Slim NVMe enclosure, while ORICO offers an active fan-cooled enclosure.
Common Storage Migration Questions
Is a 10Gbps magnetic SSD fast enough for ProRes recording?
StorageReview places 4K60 ProRes 422 HQ capture at approximately 220 MB/s, allowing a 10Gbps connection to operate well below its maximum theoretical throughput.
Do magnetic phone SSDs work with the iPhone 18 Pro?
Manufacturer documentation from SanDisk names the iPhone 15, 16, and 17 Pro and Pro Max lines, with no official confirmation listed for the iPhone 18 Pro or iPhone 18 Pro Max.
What separates sealed USB4 drives from DIY M.2 enclosures?
Sealed USB4 drives arrive pre-assembled with manufacturer warranties and encryption support, whereas DIY enclosures require purchasing separate NVMe modules during periods of fluctuating retail stock.
Do portable SSDs slow down as capacity fills?
StorageReview observed sequential write speeds dropping significantly on the Samsung P9 once the drive approached maximum capacity.
Worth a look