The MyDigitalSSD SBX SSD Review: NVMe On The Cheap
by Billy Tallis on May 1, 2018 8:05 AM ESTSequential 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%.
The burst sequential read speed of the MyDigitalSSD SBX is clearly faster than what SATA drives offer, but the Samsung drives and even the larger capacities of the Intel SSD 760p are in an entirely different league. The Phison E7 drives with planar MLC offer about the same performance as the SBX.
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.
The flash is clearly much more of a bottleneck than the PCIe x2 interface on the longer sequential read test, where the internal fragmentation left over from the random write test prevents the SBX from delivering data any faster than the SATA SSDs. The Intel SSD 760p performs even worse at 128GB, but beats the SBX at 512GB.
Power Efficiency in MB/s/W | Average Power in W |
Power efficiency continues to be a downside to the MyDigitalSSD SBX even though its power draw in absolute terms is substantially lower than the other NVMe drives. The Intel 760p is clearly worse off this time with much lower efficiency at every capacity, while Samsung's high-end drives are fast enough to offer efficiency as good or better than SATA drives.
The sequential read performance of the SBX improves a bit between QD2 and QD8, allowing it to eventually surpass the Intel 760p that is generally better at QD1 but doesn't scale up with higher queue depths.
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.
The burst sequential write speed of the MyDigitalSSD SBX exceeds that of SATA SSDs, though only barely in the case of the 128GB SBX. The 128GB Intel 760p fails to keep up with mainstream SATA drives, while the larger capacities have a clear lead over the SBX.
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.
On the longer sequential write test, only the 512GB SBX is able to stay ahead of mainstream SATA SSDs. The Intel 760p has a minimal performance lead over the SBX at 128GB, growing to a 22% advantage at 512GB.
Power Efficiency in MB/s/W | Average Power in W |
The MyDitigalSSD SBX's power efficiency during sequential writes is better than Intel's drives, but not much else. The SBX is paying the power cost of PCIe (albeit only two lanes) but delivering SATA performance.
The MyDigitalSSD SBX delivers essentially the same sequential write performance at all tested queue depths, and power usage is also flat. The results from the SBX are most comparable to mainstream SATA drives, while the high-end NVMe drives are generally much faster and more power hungry.
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Samus - Tuesday, May 1, 2018 - link
Ditto. I think it'd crazy to use a 2.5" over an M2 if you have the M2 slot available, especially since M2 SATA drives are often cheaper than 2.5" drives (because they are less expensive to manufacture, and the OEM market is larger.)And as far as SATA M2 drives, if you have an M2 slot that supports NVMe, it's hard to justify not using an NVMe SSD when the cost difference is less than 20%...I picked up the WD Black 512GB NVMe drive last week for $150. A decent 540GB class SATA M2 SSD is at least $120.
Death666Angel - Tuesday, May 1, 2018 - link
If every dollar counts and the performance increase is small or won't be used, it's pretty easy to justify getting a SATA M.2 drive instead of an NVME one.Death666Angel - Tuesday, May 1, 2018 - link
Especially since small capacities are likely to be very close in speed, when comparing NMVE and SATA M.2.Byte - Tuesday, May 1, 2018 - link
As someone who does a lot of testing/tweaking, i love the easy formfactor, but hate having to screw and unscrew. We really need a tooless update.MajGenRelativity - Thursday, May 3, 2018 - link
Honestly, I find it about the same amount of time/difficulty to (un)screw an M.2 drive as it is to work with even a toolless 2.5" drive. Unless the M.2 drive is under the GPU, in which case that really annoys meleexgx - Tuesday, May 1, 2018 - link
Still £/$30 more for a customer who is not going to benefit from the nvme ssd (and less money for you)I hardly notice the difference between the sata and nvme ssd my self, main difference is them above 1GB/s speeds but day to day usage I don't really notice much the difference between them unless I am looking for the difference (as long as it's Not a HDD even a slow ssd is many times faster then a hdd)
Do Samsung 850 evo have am issue if they have been left on for to long (like 30 days) as my 850 evo just crap it self out smart fail at Bios and can't read it (only done basic not hirions boot CD yet)
MajGenRelativity - Thursday, May 3, 2018 - link
Actually, I'd technically make a little more money if I sold them an NVMe SSD (my labor cost scales with price of parts), but they wouldn't benefit from it, so I generally don't recommend them. 850 Evo's don't normally have that issue.peevee - Tuesday, May 1, 2018 - link
AT, how about a couple of user-reproducible, real life tests? Compilation of a large software package. Unzipping a large archive. Recoding video. Just to demonstrate the scale of improvement the buyers could actually SEE.SanX - Wednesday, May 2, 2018 - link
Two reasons come instantly. Because only salespeople left in IT. No one even discuss calling lawyers for such confusing people blatant claims like 1600MB/second read speed this product has. And because Windows for example will load something like in 17.6 seconds instead of 17.9 with this drive vs SSD.Funny also is that 2-3 times slower drive which does not deliver at all is just 25-30% cheaper then the leaders.
peevee - Friday, May 4, 2018 - link
This site is often for people for assemble their own PCs and/or choose what to buy for their companies. I'd think a few reproducible, real life tests vs proprietary and compressed tests would show the value of improvements.Maybe it is what AT really is afraid of, because tests show the improvements which do not exist in real life?