Samsung 990 Pro vs WD Black SN850X: Which NVMe SSD to Buy in 2026?
The two best PCIe 4.0 SSDs go head-to-head. We compare speed, thermals, price and durability to help you pick the right one.
| Spec | Samsung 990 Pro 2TBSamsung | WD Black SN850X 2TBWD |
|---|---|---|
| Sequential Read | 7,450 MB/s | 7,300 MB/s |
| Sequential Write | 6,900 MB/s | 7,100 MB/s |
| Random Read IOPS | 1,400K | 1,200K |
| TBW (2TB) | 1,200 TBW | 1,200 TBW |
| Price (approx.) | ~$130 USD | ~$120 USD |
| Warranty | 5 years | 5 years |
| Max temp. | 70°C | 70°C |
| Heatsink included | Pro version | Gaming version |
Real-world performance
In synthetic benchmarks, the 990 Pro wins on read IOPS, the SN850X wins on write speeds. In actual day-to-day use on a gaming PC or PS5, the difference is undetectable.
For game loading, open-world streaming, or everyday file transfers, both drives perform identically. Speed differences only appear in benchmarks or large file transfers (50+ GB).
Which one to buy?
Choose the Samsung 990 Pro if:
- You want the most proven, recognizable brand
- You prioritize read IOPS (databases, many small files)
- You're in the Samsung ecosystem
Choose the WD Black SN850X if:
- You want to save $10–15 USD
- You need sustained high write speeds
- You're using it in a PS5 (dedicated PS5 version with integrated heatsink)
Frequently asked questions
Does either drive need a heatsink to avoid throttling? Not strictly — both are rated to handle sustained loads without a dedicated heatsink in a case with reasonable airflow, and both throttle gracefully (rather than crashing) if they do get too hot. A heatsink mainly helps in poorly-ventilated cases or during very long sustained writes (large video exports, big game downloads back-to-back).
Is the difference between these two drives noticeable in everyday use? Almost never. Both are well past the point of diminishing returns for typical use — booting Windows, loading games, opening applications. The gap only shows up in large sequential transfers (50GB+) or heavy multitasking with many simultaneous read/write operations, like professional video editing.
Which one is better for a PS5? The WD Black SN850X has a specific "for PS5" version with a factory-installed low-profile heatsink sized to fit the console's expansion bay exactly, which makes installation slightly simpler — though the standard 990 Pro heatsink version also fits and performs just as well.