Sabrent rocket 4 plus 2TB review


Becuase my computer was running out of space i decided to add an overpriced SSD. My case has very poor airflow (no additional fans installed yet) i decided against the more expensive and hotter running western digital SN850 2TB. I cloned the old windows 10 disk using the software sabrent provided but then when i started testing the drive it did not perform good at all.


It turns out for best performance you need to use the "defragment and optimize drives" tool in windows 10. I also changed the power setting to "ultimate performance". Results still wasn't good


I ended up contacting sabrent costumer support but the individual basicially told me to make sure Trimp was enabled (it was already) and use "defragment and optimize drives" (which i had already done). Then he basically suggested making a clean install of windows 10, well they never mentioned you had to re-install windows to get the performance you paid for.

I also tried moving a 139GB folder and it took 2 minutes and 45 seconds with 900GiB of Free space.


To test this i booted via my old slow samsung 850 evo and ran tests from there


It turned out however that he was simply wrong, my SSD was not functioning properly and the issue was windows 10


By checking the "Turn off windows write-cache buffer flushing" box you do however slighly increase the risk of data-loss in some scenarious but if you actually want to protect your data you should do an actual proper backup. This unfortunatily didn't completely fix the issue of inconsistent performance, the performance will still drop badly once the SLC cache is filled. To get to these settings search for "diskmgmnt" in the start manu and continue from there.

The time to copy 139GiB dropped down to 129 seconds (from 165 seconds)

Synthetic benchmark also improved significantly and results became less inconsistent


This is similar (still a bit worse) to what a professional reviewer got:

I noticed during testing that the randon write speed was CPU limited meaning you need a better CPU than r5 3600 to take full usage of the Rocket 4 plus 2TB


Despite extensive usage it only reached the critical temperature (70 °C) 12 minutes.


TBW in the picture above is the number of TeraBytes (not TiB) written divided by 140, when that number reaches 10 your warranty is gone, this is bad but the competition is even worse (not by much).



Cheap nand flash?
One explanation for why the warranty is limited to 1400 TBW (compared to 3600 for their older model) is that they simply use cheaper flash now and still cranks out better performance due to having a superior controller, another potential explanation is that their competition is even worse (1200 for the 2TB models) while being more expensive so they could get away with bad warranty.

In any case 1400 TBW warranty is not good at all, if i continue using the drive at this pase warranty will be gone in just 800 days.

It may be the case that they originally planned to use better nand but they decided to release the prototype version since just that was enough to match the competition (while being cheaper). The performance is almost identical to the early samples sabrent sent out to reviewers.

Current version of the rocket 4 plus is only really good as a budget price and it could remain a viable option for people unwilling to pay more money to get proper sustained write speed.

NewMaxx wrote:

Reviewers might have a better idea than I do, which would include /u/TurboSSD (he's also on discord). The drive is being discussed on the Facebook SSD group so maybe someone will chime in there, too. I've previously read there that the new flash version of the Rocket 4 Plus is due as early as March as well.

Upgrading flash over time isn't new, we saw the E12 drives go from 64L to 96L, most or many SATA drives (like the MX500) have migrated to 96L flash (with the SU800 having migrated from 32L!), etc. Production is moving away from 64L (there's oversupply in fact) and even 96L as flash manufacturers are pushing 112/128L or 176L.

I'm not specifically referring to Sabrent's Rocket 4 Plus here as what I heard was E18 in general but I would be surprised if they didn't eventually change over. Most of the flash we're seeing on Gen4 drives is B27B which is a minor modified variant of B27A, 96L Intel/Micron TLC that has been around for a long time (it is on the A2000 for example). The SN850 is using BiCS4 which is the same generation as what's on the SN550 and SN730/AN1500. In fact the only Gen4 drive with newer flash is the 980 PRO so far.

Point being, the events of 2020 have further delayed the arrival of newer flash, so we're caught with many new controllers (8/12/16nm designs included) that have to rely on older flash for the time being. Considering that production of said drives is still relatively small, that's not a big deal. In fact the E18 is still going through firmware changes (as may be the SM2264). So really Gen4 just isn't ready yet.


The registration process
Sabrent require that you register your product to get 5 year warranty rather than the standard 1 year, unfortunatily the registration process is very inconvenient.


They do not tell where do find the product serial number, i entered the number on the package (12 digits) nd then i registered again using the number crystaldiskinfo provided, i am not sure which (if any) are correct. They do not tell you if you enter incorrect info so you can only hope you got it right


Unless you need more space right now your best option is probably to wait for something better. most people that buy this drive are probably not going to take the complicated and unspecified steps needed to get the performance they paid for. If it wasn't for the fact that it runs cool (even with bad airflow without heat sink) i would have recommended against buying it.

Performance: 80%
value: 70%
Warranty: 40%
convenience: 40%
costumer support: 40%

They need to fix their software, a firmware update might also be required to reach the full performance potential.


Old vs new partition
I did copy the partition via the xcopy command which took about 2 hours and 5 minutes. Then when i began to test the performance i found out that it didn't improve, instead results were a bit random and it was difficult to observe any pattern.




Its unclear why the performance of the old partition became good out of a sudden, there was just 34.8GiB free space.

The performance of the new partition became consistent after deleting a dublicated 20GiB folder

Same thing happened with the old partition, it just needed a little bit more free space


50.4 folder copy test
During the first test there was a write performance inconsistency but this didn't happen during the second or third test.


50.4    time   transfer rate
Test 1  44s    1173 MiB/s
Test 2  29.3s  1761 MiB/s
Test 3  28.4s  1817 MiB/s
This was with 867 GiB of free space and running the operating system (plus 2 browsers) from the drive while i was testing it.

IN 2 of 3 tests i got better performance than the following professional benchmark

So despite copying a larger folder with 78 items instead of 7 and also using the disk to run windows (and other things) the transfer time i got was better than the professional benchmark above in 2 tests, this is however after disabling write-cache buffer flushing.


50.5 GiB folder copy test
Now it was time to test the drive harder by moving a lot more files.


50.5   Time   transfer rate
test1  43.9s  1178 MiB/s
test2  47s    1100 MiB/s
test3  42.4s  1229 MiB/s


50 GiB folder copy test
Increasing the number of files further grinded the performance down to a halt, the SSD need large files to deliver good performance (up to 1.8 GiB/s).


Third copy test (50 GiB)


First copy test (50 GiB)

50     Time TransferRate
test1  97s  528 MiB/s
test2  89s  575 MiB/s
test3  95s  538 MiB/s
This is not a good result.

I assume the disks where empty with no operating system running on them but they do not get into this in the review

Their 50GB dataset includes 31,227 files of various types, like pictures, PDFs, and videos.


Random read and write was CPU limited
I found this out by increasing the number of threads in CrystalDiskMark to 12 and running the random 4k Q32 test.



Sabrent rocket 4 plus vs Ram Disk
Benchmark like atto have "direct I/O" enabled by default that will bypass the operating system, this was disabled and the performance was compared to a ram disk, no difference.



There was some difference in file copy tests but i was unable to reach above 2.3 GiB/s even when only copying withing the ram disk.

This tells us that speeds above 2.3 GiB/s are essentially wasted and that the most important thing with an SSD is to deliver at least 2GIB/s consistently and unfortunatily sabrent rocket 4 plus fails to do that and therefore i will try to return it for a full refund.

It will take some time before we see programs take a decent usage of fast SSDs (direct storage, etc) but right now consistency is the most important factor.


Linux ext4 file copy test
The file copy transfer rate was at best 2.3 GiB/s but got significantly worse once the drive ran out of SLC cache.



Tests using FastCopy
There is one windows programs that will offer significantly better speeds when copying files but unfortunatily its not particularly convenient to use, what we need is an program integrated in windows explorer or a stand-alone file manager.

The following test was done with FastCopy running the operating system from another drive, this is the moment of truth:



View attachment 481

Read: 6495 MiB/s
Write: 4632 MiB/s
Mixed: 2756 MiB/s

Still despite these improvements there was still clear bottlenecks, copying a file within the ram disk gave an average of 3793 MiB/s which of course doesn't actually make any sense, it shouldn't be slower to copy a file within the ram disk than to copy a file from an NVME to a ram disk.


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How the high performance helps in real usage
While a single process will typically be cpu bottlenecked by only utilizing one core (plus other windows 10 nonsense) the disk will still be ready to handle other things at the same time.

Otherwise if you have a slower SSD that is fully utilized by a single process then if you try to do something else you will face slowdowns since the disk was already at 100%.

Better sequantial writes when using the SLC cache wouldnä't even be that helpful since then the SLC cache would just be used up faster.


SSD was returned to amazon
This was not an easy decision given the lack of fast 2TB alternatives and the fact that my current SSDs are far worse in pretty much every way.

samsung 850 evo.png

This is me moving back files to my samsung 850 evo, its painfully slow and probably cannot be fixed.

It seems like amazon is already selling my SSD not telling people it isn't completely new. This would explain why they suddenly have one in stock while previously having none in stock and claiming "will get in stock januari 17".


There are already several SSDs that have sustained write speeds i view as acceptable but these SSDs do however have other issues, there is not yet any 2TB version of samsung 980 pro and its unclear what the sustained writes are for SN850. Older drives only support pci express generation 3

Adata gammix S70 2TB is already out on the market but its more expensive and it has not yet been independently tested, like sabrent and western digital they have not released any figures for sustained write speed so its probably bad.

Holdoooo wrote:

SM2264 was officially launched last year. I guess now we're waiting for the new flash and actual SSDs?

NewMaxx wrote:

It's in reviewer hands (by way of the S70), I'm simply stating that it's still with 96L flash as far as I know. It's intended to be paired with Micron's upcoming 176L however. That will happen later.


Despite my case having zero additional fans i never got to the point where the SSD throttled due to heat.
I later got told that it throttled at 70° C and that this is what it means by "warning temperature" i wrongly assumed it only throttled at "critical temperature" (110 °C), i did not properly measure the temperature and i was unable to find any more recent saved stats tnan the following



Messages from tomshardware reviewer
He concluded that the severe slowdowns is from termal throttling and not the drive running out of SLC cache.

TurboSSD wrote:

After doing about 200-250GB of writes with no airflow mine starts to degrade due to thermal constraints based on that hard 70C limit. Even in a 23C room with two 120mm fans aimed directly at it, I couldn’t saturate the cache without thermal throttling on the 2TB model.

Here you can see the thermal throttling -

Ignore the first portion of the test where it's really slow and ramping up, this was a "dirty" (run only trim not secure erase). Once it ramps up to speed of 6.5-6.8GBps it can hold it for a few hundred GB, but once the reported temp hits 70C it will scale down performance to keep it there - you can see the performance scale down after 300GB of writes here until the cache fills to about 700GB.

For most workloads, it normally will not throttle. I need to test more GEN4 to gen 4 interaction once I update my system with a 5900X and newest X570 firmware, but most of the time my single transfers are like 1.5-2 GBps at most and in order to attain higher I have to break down transfers into like 2-3 in order to saturate bandwidth