Samsung PM9B1 (OEM) 512 GB vs Kioxia BG4 (OEM) 512 GB
Short answer: which is best?
Samsung PM9B1 (OEM) 512 GB is 27.6 % stronger than Kioxia BG4 (OEM) 512 GB. Samsung PM9B1 (OEM) 512 GB ranks #29 of 54 measured system drives at WhatFPS (8,373 Drive score over 3 verified runs). Kioxia BG4 (OEM) 512 GB ranks #45 of 54 measured system drives at WhatFPS (6,560 Drive score over 2 verified runs). The numbers are measured in 5 verified WhatFPS runs — not estimated, not self-reported.
Measured comparison
| Metric | Samsung PM9B1 (OEM) 512 GB | Kioxia BG4 (OEM) 512 GB |
|---|---|---|
| Drive score (the drive's own performance: sequential read + 4K IOPS) | 8,373 | 6,560 |
| Best rig (GAMING — whole PC) | 3,718 | 5,789 |
| Sequential read | 1,895 MB/s | 1,579 MB/s |
| 4K IOPS | 10,418 | 9,535 |
| 4K latency, median (lower is better) | 89 µs | 92 µs |
| Type | NVMe SSD | NVMe SSD |
| Size | 512 GB | 512 GB |
What the numbers mean
The drive score is the system drive's measured performance in the rigs it sat in — sequential read and 4K IOPS, unbuffered. PCIe generation, fill level and driver affect it. GAMING is the whole rig's score. We show both and never mix them.
All numbers come from our benchmark suite, the same test on every PC, written in Rust with no middleware. The methodology is open at https://whatfps.com/metodik
All measurements for Samsung PM9B1 (OEM) 512 GB · All measurements for Kioxia BG4 (OEM) 512 GB