Dark Green Spots

[Represent808]

Firstly, thank you to the developers for the software. I had a pending sector count of 11. Various ways of low level formatting could not fix the HDD (WD 5TB Black Game Driive used for continuous Macrium Reflectr imagaing backups) until using your software. Those 11 pending sectors are now gone. But I noticed the dark green boxes (very slow speed) as the test was coming to an end. Is this a cause for further concern? What is the reason for them? I have already started to use the drive again but is there soemthing I should do to test those sectors? OR is it too late without wiping the drive again?

BTW I am a tech novice. Not well notviced with HDDs so explanations in simple terms will sink in better. Thanks in advance!

[hdsentinel]

Thanks for your message and your kind words, really appreciated

No need to worry, what you see is completely normal and expected on this drive (and other drives using SMR technology). On these drives during very intensive disk write operation (for example during the Reinitialise Disk Surface test) the drive seems fast when the test started - then the performance seems lower at the end of the test. This does not mean problem with the "end" of the drive, just the drive need to perform background activity (like flushing a cache) and this causes that any current disk operation seems slower.

If there is no yellow / red blocks, then things are fine, no need to worry.

You can check some topics in this forum, showing similar situations and explain the details:

https://www.hdsentinel.com/forum/viewtopic.php?p=20838
https://www.hdsentinel.com/forum/viewtopic.php?p=20805#p20805

If you are interested in the technical background, you can read:

https://zonedstorage.io/docs/introduction/smr

which explains how these drives work, what is SMR hard disk drive in general.

[Represent808]

Thank you very much for your response. That is comforting to know the drive is OK. Out of curiosity, what could have caused the pending sector issue with the drive? Was it due to the constant Macrium usage? or somthing else?

Also what exactly is the difference between a low level format and a HD Sentinel Reinitialize Disk Surface? Beecause the latter worked and 3 runs of the former did nothing!

[hdsentinel]

In most cases, the current pending sector count increases when the operating environment is not 100% stable: cables, connections, insufficient power (or sudden power loss) are frequent causes.

This is especially common with external 2.5" USB hard disk drive (especially a such high capacity hard disk drive, like yours) as these drives are very sensitive to fluctuations of power on the USB line. USB hub, USB extender cable can cause similar.
Connecting such drive to front panel USB 3.0 connection (or any USB 2.0 connection) may cause similar too, as then the drive may not receive enough power for proper operation. The "best" is that the current pending sector count may increase much later (weeks/months later), not immediately.

The bottom of the page
https://www.hdsentinel.com/hard_disk_case_weak_sectors.php
shows some tips about what to do, how to avoid them in general (mostly for internal drives).


The Reinitialize Disk Surface test performs mutliple overwrite passes with special patterns, exactly to allow the drive to recognise the problem and fix the pending sector. Yes, some other tools may (incorrectly) call a simpler, less effective function as low level format.

[Represent808]

Super. Thank you so much. Purhase of the software was well well worth it!