WD80EDAZ & WD80EDBZ donor head compatibility

[cheadledatarecovery]

I've worked on a few WD80EDAZ, but I've just received in a WD80EDBZ with failed heads. These disks look largely similar to each other, but the EDBZ has a higher spindle motor speed.

Has anyone tried changing the heads between them to see if there is cross-compatibility?

Best regards,
John

[Doomer]

Yes, they work
But they are both 7200rpm

You might want to add numbers and letters after the dash in the model name for a better identification.

[fzabkar]

A new twist to IntelliPower?

https://forum.hddguru.com/viewtopic.php?f=3&t=38333

Many of WD's "5400 RPM class" HDDs are just crippled versions of their 7200 RPM models.

[cheadledatarecovery]

Hello Doomer,

Thanks for the info.

The reason I thought the WD80EDAZ has a lower spindle speed was because UFS Explorer was reporting it at 5640 RPM, see screenshot with a EDAZ via USB. However, thanks to your and Fzabkar's information and a quick Google search I can see that WD have had some issues where the EDAZ drives reported spindle speed is not necessarily what it appears.

Best regards,
John

Attachments

[fzabkar]

US7SAN8T0 = Ultrastar DC HC320

https://documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/product/data-center-drives/ultrastar-dc-hc300-series/product-manual-ultrastar-dc-hc320-sata-oem-spec.pdf

WD usually writes "5400 RPM class" on the label when they obfuscate the real RPM. Your drive doesn't seem to follow this pattern.

[Doomer]

There are different WD80EDAZ models
WD80EDAZ-11TA3A0 - HGST Vela-AP, 7200 rpm, CMR
WD80EDAZ-11CEWB0 - WD Avalon RP, 5640 rpm, SMR (CMR emulation)

They use the same hardware, heads are compatible.
But your WD80EDBZ is likely an HGST model, these drives are hard to deal with, simple head replacement usually does not work.

[cheadledatarecovery]

Yes, the failed WD80EDBZ-11B0ZA0 I have in has typical HGST part number markings / construction. Date of manufacture 08 FEB 2023. It came from a WD My Book which took a physical shock. It was of some relief that it wasn't a helium filled disk in the caddy, but from what you state it sounds like this could be challenging and lack of support in PC3000 will not help.

I've not looked at the structure of the NV-RAM/ROM in these very new HGST(WD) disks. Does the prevention of a simple head replacement relate to some adaptives that have been added? Sounds like some R&D on these drives is going to be required.

The WD80EDAZ-11CEWB0 in the caddy was a working disk I held in stock for return media.

[fzabkar]

I've not looked at the structure of the NV-RAM/ROM in these very new HGST(WD) disks. Does the prevention of a simple head replacement relate to some adaptives that have been added? Sounds like some R&D on these drives is going to be required.

I have written tools to extract the component modules from these new ROMs and also from firmware updates. I also have SA dumps from some SAS models which use a similar firmware architecture. If you can dump the ROMs, I can analyse them for you.

[Doomer]

Yes, the failed WD80EDBZ-11B0ZA0 I have in has typical HGST part number markings / construction.

It's HGST Vela-AP drive.

It came from a WD My Book which took a physical shock.

If heads are torn - write it off.

[cheadledatarecovery]

Thanks Fzabkar for the offer and Doomer on your advice. I'm currently waiting on paperwork/authorisation from the customer before a full disassembly of the disk. Once received I'll investigate the disk fully. Given the disk was knocked over whilst powered on, there is the prospect of damage to a platter surface.

Best regards,
John

[Doomer]

Thanks Fzabkar for the offer and Doomer on your advice. I'm currently waiting on paperwork/authorisation from the customer before a full disassembly of the disk. Once received I'll investigate the disk fully. Given the disk was knocked over whilst powered on, there is the prospect of damage to a platter surface.

Best regards,
John

if you disassemble the platters packet you can write it off for sure.

[colanco]

There are different WD80EDAZ models
WD80EDAZ-11TA3A0 - HGST Vela-AP, 7200 rpm, CMR
WD80EDAZ-11CEWB0 - WD Avalon RP, 5640 rpm, SMR (CMR emulation)

Interesting ...... which firmware modules would be related to this????.

[ed_co]

There are different WD80EDAZ models
WD80EDAZ-11TA3A0 - HGST Vela-AP, 7200 rpm, CMR
WD80EDAZ-11CEWB0 - WD Avalon RP, 5640 rpm, SMR (CMR emulation)

They use the same hardware, heads are compatible.
But your WD80EDBZ is likely an HGST model, these drives are hard to deal with, simple head replacement usually does not work.

First of all thanks for the information about the WD80EDAZ-11CEWB0 drive, there is nothing out there about this drive is SMR except here.
Could you please link to technical docs about the drive? Would love to know more about what CMR emulation is and what is the impact in the performance.
And even if it is just firmware, if could be reflashed to make it pure CMR (just checking, although I am almost sure is not possible).

Thanks

[gps31]

Is there any possibility to get the firmware backup of WD80EDAZ-11CEWB0?