Sequential Read Performance

Our first test of sequential read performance uses short bursts of 128MB, issued as 128kB operations with no queuing. The test averages performance across eight bursts for a total of 1GB of data transferred from a drive containing 16GB of data. Between each burst the drive is given enough idle time to keep the overall duty cycle at 20%.

Burst 128kB Sequential Read (Queue Depth 1)

The Samsung PM981 set new records for burst sequential read performance, but the Samsung 970 EVO fails to live up to that standard. The 970 EVO is a substantial improvement over the 960 EVO, but doesn't manage to beat the last generation's fastest MLC drives.

Our test of sustained sequential reads uses queue depths from 1 to 32, with the performance and power scores computed as the average of QD1, QD2 and QD4. Each queue depth is tested for up to one minute or 32GB transferred, from a drive containing 64GB of data.

Sustained 128kB Sequential Read

On the longer sequential read test, the Samsung 970 EVO performs far better than the Samsung PM981, indicating that Samsung has made significant firmware tweaks to improve how the drive handles the internal fragmentation left over from running the random I/O tests. The 970 EVO is the fastest TLC-based drive on this test, and the 1TB model even manages to beat the MLC-based 1TB 960 PRO.

Sustained 128kB Sequential Read (Power Efficiency)
Power Efficiency in MB/s/W Average Power in W

The 1TB 970 EVO draws more power during this sequential read test than any other M.2 drive in this mix, but its performance is high enough to leave it with a good efficiency score. The 500GB 970 EVO ends up with below-average efficiency.

Both capacities of the Samsung 970 EVO have very steady performance and power consumption across the duration of the sequential read test. This is in contrast to drives like the WD Black and Toshiba XG5 that don't reach full performance until the queue depths are rather high.

Sequential Write Performance

Our test of sequential write burst performance is structured identically to the sequential read burst performance test save for the direction of the data transfer. Each burst writes 128MB as 128kB operations issued at QD1, for a total of 1GB of data written to a drive containing 16GB of data.

Burst 128kB Sequential Write (Queue Depth 1)

The burst sequential write performance of the Samsung 970 EVO tops the charts, with the 500GB model almost reaching 2.5GB/s where the last generation of drives couldn't hit 2GB/s. The WD Black is only slightly behind the 970 EVO.

Our test of sustained sequential writes is structured identically to our sustained sequential read test, save for the direction of the data transfers. Queue depths range from 1 to 32 and each queue depth is tested for up to one minute or 32GB, followed by up to one minute of idle time for the drive to cool off and perform garbage collection. The test is confined to a 64GB span of the drive.

Sustained 128kB Sequential Write

On the longer sequential write test, the 1TB 970 EVO takes a clear lead over everything else, even the 1TB PM981. The 500GB model is handicapped by its smaller capacity and smaller SLC cache, but still manages to be significantly faster than the 512GB PM981.

Sustained 128kB Sequential Write (Power Efficiency)
Power Efficiency in MB/s/W Average Power in W

The 970 EVO and PM981 offer almost exactly the same power efficiency on the sequential write test. The 1TB model is slightly less efficient than the WD Black and 960 PRO, while the 500GB model is well behind the MLC-based drives of similar capacity.

The 1TB 970 EVO starts off with a much higher QD1 performance on the sequential write test than the PM981 offers, and at higher queue depths it maintains a slight lead. At 500GB, the 970 EVO's performance oscillates as only some portions of the test are hitting the SLC cache.

Random Performance Mixed Read/Write Performance
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  • mapesdhs - Sunday, May 6, 2018 - link

    HollyDOL, as others have said, it very much depends on what you're doing. As a C-drive it simply helps to have any kind of SSD at all rather than a rust spinner (except of course the cheap junk knockoffs like Gloway). The Vertex3 was a pretty good SSD for its time (I have lots of them), though back then the Vertex4 presented its own significant bump up in benchmark performance, as did the Vector. For general use, you might notice some difference compared to an NVMe device, certainly in bootup times, but beyond that it depends on the task. Some games will certainly load a lot quicker, assuming the CPU/RAM are able to take advantage of it. And btw, some older mbds can have a mod BIOS installed to enable booting from NVMe (I'm more familiar with the options for ASUS boards in this regard), and certain NVMe SSDs even have their own boot ROM (eg. 950 Pro) such that native boot support isn't required.

    It's a good idea for video editing though, eg. the main cache/scratch drive for After Effects or Vegas.
  • Lolimaster - Tuesday, April 24, 2018 - link

    Unless you work moving huge chunks of data (editing 4k for example) a lot there's no point going NVME over the Crucial MX500 sata.
  • Death666Angel - Tuesday, April 24, 2018 - link

    Especially in cramped cases, small form factor stuff, the gum stick is really nice because you don't need annoying cables around. My next MoBo will be some Ryzen thing in mATX with 2 M.2 slots (likely PCIe and SATA), so I can go all SSD for my desktop without any cables. I haven't noticed improvements after going to SATA3 SSDs from my Vertex/Agility first gen ones.
  • iwod - Saturday, April 28, 2018 - link

    I can't disagree more. SATA is limited in Seq speed. And it is actually a user observable difference in everyday use, between a 1.5 - 2GB/s and 600MB/s speed.

    Now whether that is worth a little more money you paid for is a different question.
  • peevee - Monday, April 30, 2018 - link

    And how you are going to hit the seq speed in real life? All external (USB or network) sources and targets are slower. Writing does not matter with write-back OS caching. Reading a document into memory is limited by memory size and actually parsing/decompression of the document. Unless you are copying huge files between RAM drives and your SSD, you have no use case. That is why the tests are generating random data on the fly, like NOTHING does in real life. And that is why sites like AT have NO reproducible real-life tests (like compilation of a large software package for example, or recoding of video), as they would show about 0 real difference between drives 2x in price.
  • mapesdhs - Sunday, May 6, 2018 - link

    I see a nice difference when cloning my photo/video archive (1TB SM961), moving files around, network access, etc., to the extent I'm now looking into 10GigE.
  • Lolimaster - Tuesday, April 24, 2018 - link

    You don't see everyday benefits because the things that make SSD's faster than HDD's (access times, random 4k QD1 reads) barely improves from sata to nvme. Even with an optane SSD you won't see much improvement.
  • Lolimaster - Tuesday, April 24, 2018 - link

    1-SSD had 100x less access time vs HDD and 100x higher 4k random performance, NVME basically only improves on sustained transfer raters.

    Going from 5-10ms to 0.07ms and from 400KB/s to 40MB/s~ was a lot.
  • Cooe - Tuesday, April 24, 2018 - link

    Yup. Without a doubt a good NVMe is much snappier, but you have to be the right kind of PC user for the difference to be that level of obvious. Even the heaviest applications, projects, etc... open instantly or near it vs the usual couple seconds, up to a minute or so for the really beefy crap with SATA-III, so if you're well familiar with PC's & in-tune with yours' level of performance, and are somebody who's regularly booting up, closing, and switching between multiple applications, storage heavy projects, etc... NVMe provides an obviously superior experience. And even if you aren't that kind of person yet, if you have compatible hardware the price gap has shrunk enough that I'd still recommend NVMe over SATA regardless as storage loads only ever increase with time. Aka you might not be the kind of person/PC user that can/will notice it now, but in a few years chances are that you most definitely will, and'll be glad you made the choice you did.

    For most lighter users atm otoh, SATA-III's already plenty fast enough for the workloads they regularly do. And that's on top of the fact that they simply don't have the level of "PC awareness" for the difference to stand out the way it does for heavy users and PC nerds like myself. And of course, even for us heavy users & multi-taskers who get real & significant benefits from the switch, it's still nothing on the order of the HDD to SATA SSD jump which is why those not well aware of their PC's current performance level and whom aren't heavy storage users (lots of regular & concurrent file access, movement, and modification) are rather likely to not notice the improvements w/o having them explictly pointed out (ala instantaneous or near it launches of most apps, even for multiples simultaneously vs delay's of a handful of seconds to a minute+ or so for the biggies, vastly improved file copy & movement speeds, ability to maintain SATA SSD levels of responsiveness while heavy storage workload(s) are active in the background, etc...)
  • Cliff34 - Tuesday, April 24, 2018 - link

    For me, the higher premium prices for nvm ssd vs sata ssd is not worth for the performance gain. I'm sure a nvm ssd is faster but I don't want to shell out few hundreds dollars (comparing the 1td) more to have my computer a few seconds faster.

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