Power Management

Real-world client storage workloads leave SSDs idle most of the time, so the active power measurements presented earlier in this review only account for a small part of what determines a drive's suitability for battery-powered use. Especially under light use, the power efficiency of a SSD is determined mostly be how well it can save power when idle.

SATA SSDs are tested with SATA link power management disabled to measure their active idle power draw, and with it enabled for the deeper idle power consumption score and the idle wake-up latency test. Our testbed, like any ordinary desktop system, cannot trigger the deepest DevSleep idle state.

Idle power management for NVMe SSDs is far more complicated than for SATA SSDs. NVMe SSDs can support several different idle power states, and through the Autonomous Power State Transition (APST) feature the operating system can set a drive's policy for when to drop down to a lower power state. There is typically a tradeoff in that lower-power states take longer to enter and wake up from, so the choice about what power states to use may differ for desktop and notebooks.

We report two idle power measurements. Active idle is representative of a typical desktop, where none of the advanced PCIe link or NVMe power saving features are enabled and the drive is immediately ready to process new commands. The idle power consumption metric is measured with PCIe Active State Power Management L1.2 state enabled and NVMe APST enabled.

Active Idle Power Consumption (No LPM)Idle Power Consumption

The active idle power consumption of the Crucial BX300 is the same as for the BX200. Both are a bit on the high side, but there are Silicon Motion drives with both higher and lower active idle draws. With SATA link power management enabled, the BX300's idle power draw is better than average, but 20mW worse than what the BX200 and Intel 545s manage with older and newer Silicon Motion controllers.

Idle Wake-Up Latency

The BX200 had a serious problem with idle wake-up latency of over 10ms, which the BX300 has fixed. The BX300 wakes up quickly, though the drives with the Phison S10 controller are still the quickest by far.

Mixed Read/Write Performance Conclusion
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  • nathanddrews - Tuesday, August 29, 2017 - link

    SSD prices at Microcenter dropped by about 25% over the weekend (850 EVO 500GB for $139) and Amazon and Newegg are also down a bit, I assume the NAND shortage is over? Just clearing inventory? I'm really happy to see MLC back in the mix! Time to upgrade the last of the mechanical computers...
  • ddriver - Tuesday, August 29, 2017 - link

    Oh no it is not. They are gonna milk that cow until Chinese NAND gets to the market. And then they will short the price.

    On a side note, way to go Crucial - making quality products with MLC flash, with endurance worse than that of TLC flash. It is quite the achievement.
  • ddriver - Tuesday, August 29, 2017 - link

    On the bright side, it is good to see that the competition is finally catching up to samsung SATA SSDs. Be that a couple of years after they stopped developing SATA SSDs.
  • Yojimbo - Tuesday, August 29, 2017 - link

    I think Chinese production of NAND and DRAM will be by new companies operating in new foundries. Volume production probably won't be reached until 2019, and can we really be sure of what to expect when it does?
  • leexgx - Saturday, September 2, 2017 - link

    you do know that endurance actually means warranty void if you use more than the endurance rating, MLC drives norm have endurance levels of PB of data before issues start to happen

    love the BX100 for its near 0 power use when idle but it does choke a little under high load meaning i actually notice it slightly when its struggling but still its many times faster then a HDD witch can get tied up under medium loads (like windows update and store)

    be nice if they can replicate that on the BX300 (should be better than the BX100 due to SLC cache and improved controller )
  • Ryan Smith - Tuesday, August 29, 2017 - link

    The NAND shortage is definitely not over. That won't abate until some time in 2018.

    I couldn't say if it was clearing inventory, a short-term deal, or something else, but right now there's no reason to believe any kind of price cuts will stick.
  • nathanddrews - Tuesday, August 29, 2017 - link

    So what you're saying is "get it while it's hot"?
  • Ryan Smith - Wednesday, August 30, 2017 - link

    Yup.
  • BrokenCrayons - Tuesday, August 29, 2017 - link

    I picked up a 480GB Muskin Reactor Armor3D for $139 _very_ recently dropped from $149. Like you, I was wondering if the NAND shortage was coming to an end, but Ryan is in a good position to know these things so maybe there's just a good deal on at the moment.
  • Alexvrb - Tuesday, August 29, 2017 - link

    MLC or not the TLC Evo is still the better performing drive. If you're buying a ~250GB model the Evo is hands down the best option. At 500GB-1TB capacities there are a couple of cheaper options that are tempting but the Evo is still the best deal for the money IMHO until you hit 2TB class drives, where the MX300 really shines.

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