The Intel Optane SSD 900p 480GB Review: Diving Deeper Into 3D XPoint

Mixed Random Performance

Our test of mixed random reads and writes covers mixes varying from pure reads to pure writes at 10% increments. Each mix is tested for up to 1 minute or 32GB of data transferred. The test is conducted with a queue depth of 4, and is limited to a 64GB span of the drive. In between each mix, the drive is given idle time of up to one minute so that the overall duty cycle is 50%.

Since this mixed random I/O test is conducted at the relatively low queue depth of four, the Optane SSDs have a large performance advantage, and even the tiny Optane Memory M.2 does well (though it has to run a slightly modified version of the test due to its low capacity). The Optane SSDs are more than three times faster overall than the highest-scoring flash-based SSD.

The Optane SSDs have a substantial power efficiency lead on the mixed random I/O test, but it is small enough that flash-based SSDs could conceivably catch up with a generation or two of improvements. As usual, the 480GB model has clearly lower efficiency because its minor performance advantage doesn't outweigh the power cost the extra 3D XPoint memory chips.

Intel Optane SSD 900p 480GBIntel Optane Memory 32GBIntel SSD 600p 512GBOCZ RD400 256GBSamsung 950 PRO 256GBSamsung 950 PRO 512GBSamsung 960 EVO 1TBSamsung 960 EVO 250GBSamsung 960 PRO 512GBSamsung PM981 512GBToshiba XG5 1TBIntel Optane SSD 900p 280GBIntel SSD 750 1.2TBIntel SSD 750 400GBOCZ RD400A 512GBSamsung 850 PRO 256GBSamsung 850 PRO 512GB

Both capacities of the Intel Optane SSD 900p show a modest decline in performance as the workload becomes more write-heavy, and a fairly linear increase in power consumption. The  480GB model's power consumption grows slightly faster than the 280GB model, leading to a 0.9W gap at the end of the test.

Even the Intel SSD 750 draws substantially less power for most of the test, though it catches up at the very end. The flash-based M.2 NVMe SSDs are mostly drawing a fraction of what the Optane SSDs require. In terms of performance, none of the flash-based SSDs come at all close to the Optane SSDs until the very end of the test, where many are able to deliver good random write speed.

Mixed Sequential Performance

Our test of mixed sequential reads and writes differs from the mixed random I/O test by performing 128kB sequential accesses rather than 4kB accesses at random locations, and the sequential test is conducted at queue depth 1. The range of mixes tested is the same, and the timing and limits on data transfers are also the same as above.

The Intel Optane SSD 900p is much faster on the mixed sequential I/O test than any consumer flash-based SSD. Samsung's best drives are slower by a third, and it's downhill from there for NAND flash. The 480GB model actually performed slightly worse on this test than the 280GB model, but the difference is small enough it may simply be due to variation between runs.

The power efficiency of the Optane SSD 900p on the mixed sequential I/O test is good but not quite at the top of the charts. Instead, it is on par with the Samsung 960 EVO, which sacrificed a bit of efficiency to improve performance relative to the Samsung 950 PRO.

Intel Optane SSD 900p 480GBIntel Optane Memory 32GBIntel SSD 600p 512GBOCZ RD400 256GBSamsung 950 PRO 256GBSamsung 950 PRO 512GBSamsung 960 EVO 1TBSamsung 960 EVO 250GBSamsung 960 PRO 512GBSamsung PM981 512GBToshiba XG5 1TBIntel Optane SSD 900p 280GBIntel SSD 750 1.2TBIntel SSD 750 400GBOCZ RD400A 512GBSamsung 850 PRO 256GBSamsung 850 PRO 512GB

The 280GB Optane SSD 900p was a bit faster than the 480GB overall but a bit less steady over the course of the test. The scaling of the Optane SSDs is quite similar to the results from the mixed random test: a gradual decline in performance as the proportion of writes increases, and a linear increase in power consumption. The overall performance level is significantly higher than for the random I/O test.

The flash-based SSDs can get much closer to competing with the Optane SSDs on this mixed sequential test than on the mixed random test. Several drives have sequential read speeds that approach that of the Optane SSDs, and a few have higher sequential write performance. But through the middle portions of the test, the flash-based SSDs all lose a lot of their performance for at least a few phases of the test, while the Optane SSD has no acute performance weakness.