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Corsair
Model: CSSD-EX400U1TB
| Capacity | 1TB |
| Interface | USB4 |
| Form Factor | External |
| Read Speed | 4,000 MB/s |
| Write Speed | 3,600 MB/s |
| Endurance (TBW) | 700 TB |
| Warranty | 5 Years |
High-bandwidth USB4 external SSD delivering up to 4,000MB/s reads with MagSafe compatibility. Perfect for creative professionals with Thunderbolt 4 and USB4 laptops.
See how it stacks up against competitors in our Thunderbolt External SSDs SSD comparison, or browse related SSD buying guides.
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Professional-grade USB4 storage with 4.0 GB/s reads and 3.6 GB/s writes — the Corsair Corsair EX400U USB4 keeps your creative workflow moving.
This drive delivers 4.0 GB/s reads and 3.6 GB/s writes — speeds that make external storage feel like internal. Move a 50GB 4K project in ~14 seconds or a 100GB asset library in ~28 seconds. No waiting, no proxies, no bottlenecks.
Rated at 700 TBW, this drive handles a solid mix of daily reads and writes. The 5-year warranty is well above the industry standard — a strong differentiator.
Sustained write workloads can push controller temperatures past 70°C, triggering thermal throttling that reduces throughput by 30-40%. Full metal enclosures manage heat better than slim plastic designs.
USB4 delivers the bandwidth needed for seamless playback and editing of high-bitrate media directly from the drive — no file transfer required.
The Corsair EX400U USB4 targets users who need maximum throughput from an external drive. If you edit 4K or 6K video, move large project files between workstations, or work directly from external storage, the 4,000 MB/s read speed puts this drive in elite territory for a 1.0TB portable SSD.
The 1.0TB capacity covers most daily workflows comfortably: system backups, a working photo library, a dozen game installs, or a collection of documents and media. If you need more space, higher-capacity variants of the same product line are worth considering.
One important note: reaching the full 4,000 MB/s requires a Thunderbolt 4 or USB4 host port. On a standard USB 3.2 Gen 2 port, the drive still works perfectly but negotiates down to 10 Gbps. Most laptops from 2022 onward include a compatible port on premium models, but verify your hardware before expecting peak performance.
On paper, the Corsair EX400U USB4 delivers 4,000 MB/s reads and 3,600 MB/s writes. In practice, a 50GB file — a typical 4K video project, a large game install, or a full photo shoot — transfers in ~14 seconds. A 100GB batch of raw files moves in ~28 seconds. For users who regularly shuttle large files, these transfer times are a meaningful productivity improvement over slower SATA-based externals that take 3-5x longer for the same tasks. Note: those numbers describe large sequential transfers — everyday tasks (opening documents, app launches, game loads) feel equally fast across all NVMe portables because random 4K performance is similar drive-to-drive.
At 4,000 MB/s, the controller generates significant heat during extended writes. Sustained sequential transfers of 200GB or more can push controller temperatures past 70°C, triggering thermal throttling that reduces throughput by 20-35%. The aluminum enclosure helps dissipate heat, but for sustained workloads, expect speeds to settle below the rated peak after several minutes of continuous writing.
The Corsair EX400U USB4 is rated for 700 TBW (terabytes written) endurance. To put that in perspective: if you write 50GB per day — an aggressive daily workload for most users — the drive would take approximately 38 years to reach its endurance limit. For typical use patterns involving backups, file transfers, and game storage, the 700 TBW rating provides comfortable headroom well beyond the 5-year warranty period.
| Spec | Corsair EX400U USB4 | Sabrent Rocket Nano XTRM-Q |
|---|---|---|
| Read Speed | 4,000 MB/s | 3,000 MB/s |
| Write Speed | 3,600 MB/s | 2,800 MB/s |
| Capacity | 1.0TB | 1TB |
| Interface | USB4 | USB4 |
| Endurance | 700 TBW | 700 TBW |
| Score | 9.2/10 | 9.4/10 |
The Sabrent Rocket Nano XTRM-Q scores higher in our evaluation (9.4 vs 9.2/10). While the Corsair EX400U USB4 has lower scoring, it may offer advantages in other areas like value. Review the full specifications above before deciding.
For a detailed head-to-head comparison, see our full Corsair EX400U USB4 vs Sabrent Rocket Nano XTRM-Q comparison.
| Model | Capacity | Interface | Read | Write | TBW |
|---|---|---|---|---|---|
| Corsair EX400U USB4 | 1TB | USB4 | 4,000 | 3,600 | 700 |
| Sabrent Rocket Nano XTRM-Q | 1TB | USB4 | 3,000 | 2,800 | 700 |
| LaCie Rugged SSD Pro 4TB | 4TB | Thunderbolt 3 | 2,700 | 1,900 | 2,400 |
| LaCie Rugged SSD Pro 2TB | 2TB | Thunderbolt 3 | 2,700 | 1,900 | 1,200 |
Specs shown for the closest Thunderbolt External SSDs alternatives. Full comparison table available on the compare page.
The Corsair EX400U comes in multiple capacities. Smaller sizes save money if you do not need the headroom; larger sizes drop the cost-per-TB for media libraries and Time Machine backups.
Corsair
Price as of Aug 3, 2026, 6:33 PM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.
Corsair
Price as of Aug 3, 2026, 6:33 PM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.
Corsair
Price as of Jul 3, 2026, 4:11 AM. Prices and availability are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.