high capacity HDD low noise

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high capacity HDD low noise

I never compared cost. One day sale, just over $14/TB. Today they are around $18/TB. Watch for BF discounts.

After shucking, I added my liberated 4 and 6TB drives to the external enclosure for random USB backups.
Good to know. I have no need for any storage for now, but I will be using Ultrastars for my next NAS purchase in a year or two...
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these are relabeled Ultrastars. For me, it was plug and play.

I can’t get, that it’s relabeled Ultrastar:
- when contains EMFZ in the PN =10k rpm/16MB cache model with SATA interface
- when contains EFDZ = 5.4k rpm/32MB cache model with SATA interface…. the second “F” means = Desktop/NAS RED and Ultrastar isn’t desktop, even RED.
There isn’t an official Ultrastar HDD with such setup. Then it must be different model. Don’t mention that 18TB capacity needs more than 16 or 32MB cache. It needs 512MB.
Yes, because WD is from base principle unclear company, someone can consider that PN decoding tables are too old for current models.

In real world Ultrastar series is divided into 3 main sub-series (datacentre, 3xx,5xx).

The Ultrastar SATA 3 series has just (helium filled):
- Datacentre series - max 14TB capacity. For this capacity it has 512 MB cache, 7200 rpm
- HC330 series - max 10TB capacity, 256MB cache, 7200 rpm
- HC550 series - 18TB capacity, 512MB cache, 7200 rpm
and so on, back into the history.

Even the RED Pro series has 18TB with 512MB cache and 7200rpm. Doesn’t use helium filled environment = less expensive for the manufacturing than the Ultrastars. But it is dangerous to use more than 14TB w/o helium.
WD RED doesn’t have more capacity than 10TB.

last is the price range of the WD 18TB Elements box (WDBWLG0180HBK-EESN):
- sales $340 … what is about $18.8/TB
WD Ultrastar H550 18TB SATA
- sales $450

And I can’t get that WD will put their top model Ultrastar HC550 into the Elements box. When they can use less expensive RED Pro for such purpose. Profit first 😉
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what is real purpose of the single 18TB, which you can divide into two independent parts?
These are 7200 rpm drives (reporting 5400 rpm)

Also note the R/N

My thought is that these are from the Ultrastar line, but do not undergo testing to Ultrastar specs
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Re: P/N with the ‘EDGZ’, there are plenty of old PN tables, all of them before 2012, when 18TB was just a dream and the acquisition of the HSGT was just announced.

Re: R/N with US7SAR180
I found, that this R/N is paired with P/N WUH721818ALE6L4 or WUH721818ALE6L1, both of them are valid P/Ns of Ultrastar HC550!
So, sorry @Telos for my distrust. I need update my internal DB.

Here is the evidence:

There is a question - Why?
So let’s back to my previous post:
- 18TB capacity needs helium filled environment. No doubt.
- specially when you need to operate 9(!) platters with 18 heads in same box than for 128GB ten years ago
- I really can’t understand how they produce mentioned 18TB RedPro w/o the helium. RedPro 16/18TB use EAMR principle of recording announced last year, what is used also in the HC550 (same announcement).
- so there are just two possible conclusions - they probably forgot to mention that 18/16TB RedPro are helium filled. Or it is still the same drive (HC550), just two labels.
- this is jus one and only answer why they are selling the 18TB just from one source HC550 - there is one and only helium filled 18TB with EAMR. Even with such price of the Elements case.

So thx, for this exercise!
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this is an evidence (seen in this forum frequently), that people are just magnetized with label “NAS” in the HDD model name and pay more for the same technology (in case of RedPro vs HC550 and 18TB.
Nice example of the irrational behavior.

The Screenshot is from B&H.
The rule is still valid:
don’t purchase NAS series HDDs, when you can buy an enterprise.

I checked the price of the HC550 (no SED PM) also here in EU and it’s possible to purchase for the similar (converted) value: €394. Even Exos X16 (same level) is for €382.

And IronWolf Pro same capacity/Helium filled about €477 what is similar value for the RedPro defined in this thread.

All of them have same 9 platters/18heads setup. Similar He filled technologies, same geometry, similar actuators, …

People must be crazy when they purchased the NAS series.

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