WD30NMZW-11GX6S1 (WD Elements 3TB) HDD tech specs?


#1

Hello,

Do someone know were I can find the tech spec for HDD reference WD30NMZW-11GX6S1 that is inside WD Elements 3TB / WDBU6Y0030BBK ? size of cache (I saw 128MB somewhere) but I want to know if there is some other kind of secondary cache ? is this drive a hybrid SSD+HDD ?

regards.


#2

Hi Dodfr,

The internal drive inside your external hard drive may vary depending on application. Depending on model, the internal hard drive in an external enclosure could be either SATA or native USB.

We don’t know a particular internal hard drive model, data interface, rotational speed, or cache size in the external hard drive enclosure. Dismantling any single-drive external enclosure to obtain this information will void the warranty of the hard drive.


#3

Internal drive reference is WD30NMZW-11GX6S1 but seems difficult to find tech spec, I don’t know why WD do not provide those specs.


#4

It’s definitely not a “Hybrid” HDD … if it was, they would advertise it and it would also be reflected in the price. (which would be higher)

And the cache would definitely not be 128MB. And be aware that the cache size makes no difference in performance of an external hard drive. Data rate transfer is bottlenecked at the USB transfer speed.

Interface and cache of the hard drives inside the external enclosure does not affect the performance or the data transfer rate of the external hard drive unit. (https://support.wdc.com/knowledgebase/answer.aspx?ID=1704)

WD’s “Elements” range is the cheapest (“Budget Range Hard Drive”) for basic storage. These drives have no “bells and whistles” over their more expensive cousins.


#5

The quote you copied say no performance but you forgot the note below it “With the exception of Thunderbolt, eSATA and USB 3.0 external hard drives” because the WD Elements I have is USB 3.0 and connected to USB 3.0 port so yes cache have performances effect.

Plus whenever it is only USB 2.0 it could still have some performance effect when there are a lot of head activity (seek-time) if this activity make the hard drive slower than USB 2.0 max speed (if re-read data are still in cache that mean less seek-time loss).

And the reason why I am asking all this is because this hard drive provide strange benchmarks result compared to all other mechanical non-Hybrid hard drives I have (internal or external).

For example it can provide a stable reading curve all over the disk surface that “should” not be possible with mechanical hard drives because the closer you go to inner side of the disk surface the less data you read per rotation, this HDD also provide very good results (ten times higher than usual) on CrystalDiskMark with 4K block write test.

So I am trying to find an explanation and figure out how this is possible or if this drive fools the benchmark tools (and id it does … how ?).

Hope my english is not too bad, I am not english native.


#6

WD are now using SMR (Shingled Magnetic Recording) instead of PMR (Perpendicular Magnetic Recording) on their external hdd’s. Which is most probably why you’re seeing strange benchmark results because data is handled a different way.

I know for a fact that my 4TB My Passport Ultra which is a few years old is 100% an SMR Hard Drive.

All my older WD Passports and Elements are PMR.


#7

thanks for the intel about SMR !

The main info in this article is for me “huge disadvantage new data must be re-sorted and rewritten, so that data rates fall sharply … hard drives using this technology are suitable as archive drives that are rarely written but often read,”

The purpose of this disk will be to store data as archive so it’s OK for me.

But if this slight tracks overlap trick permit to get +25% space I do not understand how this disk can provide such linear readind speed curve all over the disk surface and can write 4K block 10x faster than usual.

edit : I found a very interesting review about a Seagate SMR based HDD that explain the high performance writting 4K blocks because of big memory cache capacity of the HDD (bench showed with the Seagate show same very good 4K writing result and access time.

This is why I still think the WD Element use a big memory cache size and this 128MB may not be “impossible”.

It also explain why I saw that the WD elements supports TRIM command that is usually supported by SSD drives https://support.wdc.com/knowledgebase/answer.aspx?ID=26014

But still… in this article we see the “normal” curve performance decrease over the disk surface which is not visible with the WD Elements.


#8

I wasn’t implying or saying 128MB Cache was “impossible”

I was saying it’s highly unlikely that a WD Elements drive … which is the WD’s cheapest, and budget range of hard drive marketed as a “Basic Storage” would have a cache that high.


#9

Yes I understood the “impossible” that way too, but it was the easiest way to explain the performances, and since then I’ve been digging Pros-Cons about SMR technology and found also other testers that also found 4K writings to be 10x faster on other SMR based HDD like Seagate and those drives carry 128MB cache memory.

Anyway I am glad I learned about this SMR technology I wasn’t aware of.

But after reading the Pros/Cons about SMR I am estonished that constructors do not clearly indicate the use of SMR on the coverboxes, I think people should be informed and make a choice depending the usage they plan to have for the HDD.