Between the T9 Portable 2TB and Black SN850X 2TB, the T9 Portable 2TB comes out ahead in interface, while the Black SN850X 2TB wins on sequential read and sequential write. Overall, the T9 Portable 2TB scores 52.4 and the Black SN850X 2TB scores 69.4 on our Mars Score.
Which should you buy?
The Black SN850X 2TB is the clear pick on raw spec strength, leading by 17.0 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
Pick the T9 Portable 2TB if you care most about interface. The biggest gaps in its favor are interface.
Pick the Black SN850X 2TB if you care most about sequential read and sequential write. Its strongest claims are sequential read, sequential write.
Both ship with comparable capacity, endurance (tbw), so those specs don't separate the two — focus on the differences below.
Bottom line: the Black SN850X 2TB is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Samsung - T9 Portable 2TB wins
- ▲Interface: USB 3.2 Gen 2x2 (vs PCIe 4.0 x4).
Why WD - Black SN850X 2TB wins
- ▲Sequential read — 265.00% more. 7300 MB/s vs 2000 MB/s.
- ▲Sequential write — 238.46% more. 6600 MB/s vs 1950 MB/s.
Spec comparison
Capacity
| Spec | Samsung - T9 Portable 2TB | WD - Black SN850X 2TB |
|---|---|---|
| Capacity | 2000 GB | 2000 GB |
Performance
| Spec | Samsung - T9 Portable 2TB | WD - Black SN850X 2TB |
|---|---|---|
| Sequential read | 2000 MB/s | 7300 MB/slead |
| Sequential write | 1950 MB/s | 6600 MB/slead |
| Interface | USB 3.2 Gen 2x2lead | PCIe 4.0 x4 |
| Form factor | Portable USBlead | M.2 2280 |
Endurance
| Spec | Samsung - T9 Portable 2TB | WD - Black SN850X 2TB |
|---|---|---|
| Endurance (TBW)ⓘ | 1200 | 1200 |
| Warranty | 5 yrs | 5 yrs |
Frequently asked
Spec-level deep dives
More from the same brands
vsMars is reader-supported. When you buy through links on our site, we may earn an affiliate commission at no extra cost to you. Learn more.