Burst IO Performance

Our burst IO tests operate at queue depth 1 and perform several short data transfers interspersed with idle time. The random read and write tests consist of 32 bursts of up to 64MB each. The sequential read and write tests use eight bursts of up to 128MB each. For more details, please see the overview of our 2021 Consumer SSD Benchmark Suite.

QD1 Burst IO Performance
Random Read Random Write
Sequential Read Sequential Write

For quite a while, NVMe SSDs with Silicon Motion controllers have been delivering some of the best QD1 burst random read performance scores. The Intel SSD 670p pushes this even further, when the test is only hitting the SLC cache. When testing against an 80% full drive, the burst random read performance is faster than most other QLC drives but slower than any good TLC drive.

For QD1 random writes, the 670p is actually slightly slower than the 660p when testing a mostly-full drive, though it is again competitive with more high-end TLC drives when writing to the SLC cache. For both sequential reads and sequential writes, the 670p offers very good QD1 throughput for a PCIe 3.0 drive, and is much improved over the 660p that is seriously bottlenecked by its low-end controller.

Sustained IO Performance

Our sustained IO tests exercise a range of queue depths and transfer more data than the burst IO tests, but still have limits to keep the duration somewhat realistic. The primary scores we report are focused on the low queue depths that make up the bulk of consumer storage workloads. For more details, please see the overview of our 2021 Consumer SSD Benchmark Suite.

Sustained IO Performance
Random Read Throughput Power Efficiency
Random Write Throughput Power Efficiency
Sequential Read Throughput Power Efficiency
Sequential Write Throughput Power Efficiency

As with the burst IO scores, the longer sustained IO tests show the Intel 670p doing very well with sequential reads or writes: the performance doesn't betray the fact that it's using QLC NAND, and the power efficiency is typical of a last-generation controller. For random reads or writes, the performance at low queue depths is similarly great when testing the SLC cache, but testing across an 80% full drive knocks performance down to typical entry-level NVMe and mainstream SATA territory. Random writes in particular are disappointing on the mostly-full drive: it's slower than the 660p and the Phison E12-based Corsair MP400, though still several times faster than the DRAMless Mushkin Helix-L.

Random Read
Random Write
Sequential Read
Sequential Write

The Intel 670p is fairly well-behaved through the sustained IO tests as the queue depth ramps up. Random reads saturate around QD32, random writes around QD8, and sequential transfers at QD2. Performance is very consistent after the drive reaches its full speed; the only big drop comes at the very end of the sequential write test on a mostly-full drive, when the SLC cache finally runs out while testing at QD128. This is pretty much never going to happen during ordinary consumer workloads.

Random Read Latency

This test illustrates how drives with higher throughput don't always offer better IO latency and Quality of Service (QoS), and that latency often gets much worse when a drive is pushed to its limits. This test is more intense than real-world consumer workloads and the results can be a bit noisy, but large differences that show up clearly on a log scale plot are meaningful. For more details, please see the overview of our 2021 Consumer SSD Benchmark Suite.

Taking a closer look at random read throughput and latency, the Intel 670p fares better than most of the other QLC drives, save for the 8TB Sabrent Rocket Q. The 670p has slightly worse performance than the DRAMless TLC Mushkin Helix-L. The throughput achieved by the 670p is similar to mainstream TLC SATA drives, but the latency is considerably higher: the SATA drives are bottlenecked by the SATA link itself, while the 670p's bottleneck is on the NAND side, which causes latency to spike as the drive is pushed to its limit.

Trace Tests: AnandTech Storage Bench and PCMark 10 Advanced Synthetic Tests: Block Sizes and Cache Size Effects
Comments Locked


View All Comments

  • abufrejoval - Monday, March 1, 2021 - link

    This is the kind of article, that keeps AT at the top of my daily reading list.

    While it's technically very neutral and to the point the last paragraph almost sound a bit like good old Charly Demerjan from Semiaccurate, who barely seems to peekt out behind his self-inflicted pay wall any more.

    Nice job and I know why my last Intel SSD was a Postville, still running btw.
  • Hifihedgehog - Monday, March 1, 2021 - link

    The interwebs gifted us the nickname of Faillake to describe Skylake, but have they come up yet with a clever name to adequately describe this pricing disaster? QLC-quandry? QLC-quagmire? I honestly don't know who would buy these except for the engineering team and the most ardent fanboys. By the way, the fanboys are very ticked off today by Billy Talis' extremely honest assessment and are downvoting other people as well who are calling the pricing "horrendous."
  • Great_Scott - Tuesday, March 2, 2021 - link

    Looks like AT is alone in talking about the pricing. I typically like HH, but they are way off base on that aspect of their review. That was a bummer to discover.
  • A5 - Monday, March 1, 2021 - link

    The conclusion here is bang-on. This is a pretty good QLC drive at a terrible price. It needs to be 10 or 11 cents/GB to be a winner.
  • Glock24 - Monday, March 1, 2021 - link

    That's more expensive than some good TLC drives 🤷🏻‍♂️
  • powerarmour - Monday, March 1, 2021 - link

    I refuse out of principle to ever purchase a QLC drive.
  • Small Bison - Monday, March 1, 2021 - link

    And for this particular drive, it doesn't take much principle to buy a better-performing TLC SSD for less money.
  • Reflex - Monday, March 1, 2021 - link

    I remember when everyone said this about TLC, yet here we are...
  • JimmyZeng - Tuesday, March 2, 2021 - link

    But for TLC this phase is much shorter, QLC is around for quite a few years, yet it failed to catch on, yeah 670 is crazily priced, but even with 660/665, they never showed any pricing advantage comparing to TLC competitors, I suppose the (rough) theoretical upper limit of 33%(4bpc/3bpc) capacity/price ratio improvement of QLC over TLC is at play here.
  • utferris - Tuesday, March 2, 2021 - link

    Learn some math before posting something.
    QLC (4 bit) is double the size of TLC (3 bit), not 4/3.
    So theoretically, the same QLC flash can double the capacity than it is used as TLC. Although in reality, the cost of QLC can not go down to half of TLC, but it should be able to get close in the long run.

Log in

Don't have an account? Sign up now