4TB USB HDD, UEFI only system, weak sectors

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Aug 18, 2022
What is the best way to check and refresh the disk surface of a 4TB USB 3.0 external HDD and repair any bad or weak sectors?
I'm starting to get slowdowns reading selected files and sometimes read errors.
I would be happy to buy SpinRite 6.0 and use that but as far as I know it does not support UEFI and has some limitations with USB and 4TB drives.
I'm pragmatic. HDDs are cheap... not quite a dime a dozen, but getting there. Just buy a new drive, copy all your files to the new drive. That will have them written safely and if any fail, then you have a file to focus on for recovery, which is different than "refresh". Once the files are safely on a new device, you can "refresh" the old one by doing a full format. If doing the format poses the slightest bit of resistance, then I would chuck the old unreliable drive. Remember that having only one copy of your files (on any device) is NOT a backup.
Thanks. I bought a new external HDD and am copying over my data now.
Data is not critical. It contains disk image backup files of various computer systems I have. If needed I can remake the backup images of the systems. All of my critical data is safely backupped on 3 redundant disks of which one is kept off-site.

I don't have much trust in waiting for Spinrite 7.0 / 7.1.

I actually bought Spinrite 6.0 back in 2010 and it did not work on the hardware I then had. Steve Gibson promised a Spinrite 6.1 release which would fix my issue "soon" and I trusted him so I waited for it. When in 2014 Spinrite 6.1 was still not released I got tired waiting and finally requested a refund. (Kudos to the generous refund policy in my case)
Now it's 2022 and we don't even have Spinrite 6.1.
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Now it's 2022 and we don't even have Spinrite 6.1.
Yes, this is the problem with polymaths... everything interests them and they sometimes fall into a rabbit hole or ten. For what it's worth SQRL is very nice and works very well, it's just not adopted in the world at large [yet]. I feel pretty confident that the 6.1 beta test will start this year, and that it will be fully released early next year... but I am not a betting man.

Spinrite 6.1 still won't address UEFI interoperability, nor NVMe nor USB support. As long as SpinRite 6.1 addresses the issue of HDDs greater than 2G it will be a success for a great many users. Steve will probably need a good year or two to get comfortable will the new OS he bought to base SpinRite 7 on, so I don't expect you'll see that before 2025. Luckily, the need to support UEFI and USB can be worked around, if you're willing to buy dedicated SpinRite hardware from eBay or similar (or you already have old enough hardware sitting otherwise disused.)
Spinrite 6.1 still won't address UEFI interoperability, nor NVMe nor USB support.
I am not sure about NVMe. When I run ReadSpeed, my NVMe drive is visible via the BIOS. I thought that Steve had said that 6.1 will work on any drive that is visible to the BIOS or ReadSpeed, just possibly not at maximum speed.
I am not sure about NVMe.
Any device detected by the BIOS will support BIOS accessing to it. I don't know how the BIOS supports NVMe devices in some cases... I don't know if the device itself comes with the necessary support ROM or if it's something built into some BIOSes.

As I understand it, SpinRite only could use the BIOS up until when 6.1 is released. Using the BIOS means missing out on on speed and technical abilities that could enhance SpinRite's abilities. (Although those are still unclear as far as flash media is concerned.)
I don't have much trust in waiting for Spinrite 7.0 / 7.1.
The 7.x versions are indeed a ways off yet.

Now it's 2022 and we don't even have Spinrite 6.1.

Please see this post for a brief synopsis of why SpinRite 6.1 is taking so long: https://forums.grc.com/threads/6-1-3-years.1029/post-7547

Steve is presently working on the SpinRite 6.1 Beta 1 release. This will be a read-only scan and report (think Level 1) version that will scan a drive , report the results, and exercise the new data logging system. It will not touch any data.

Progress from now on will be slow for two reasons. For one, Steve will be exercising new code that has never been tested before.
For another, data safety and integrity will be priority 1.

We can have it fast, or we can have it good. But not both as they are mutually exclusive. Steve will be putting in a lot of time testing things on his myriad selection of hardware.
When he does release something we can have a very high degree of confidence that it will treat our valuable data safely.
When he does release something we can have a very high degree of confidence that it will treat our valuable data safely.
Not necessarily so, remember millq6.exe ? That trashed the USB drive & the boot sector of the the C drive! I think about 12 people got caught on that one including me. This is test software, so if you are going to be testing you have be prepared for things like this to happen. I run it on my old work laptop, not my everyday one (not that it could run on the new one, UEFI only!).
Not necessarily so, remember millq6.exe ?
Of Course! That was the one and only bad release out of more than 500 SR 6.1 development test releases to date. That's a very good track record, IMHO.

I think about 12 people got caught on that one including me.
There were 12 downloads. 6 were burned. 5 (including me) saw the bad news and never ran that release. There was one download that, AFAIK, was never accounted for.

My perception was that those 6 that were burned had a variety of MBR recovery tools available for free download. But still, it was a very scary trip into the unknown for them, that should not have been necessary.

This is test software, so if you are going to be testing you have be prepared for things like this to happen.
I totally agree. I have some old (expendable) machines where there is no risk of losing anything of value if the unexpected happens. I do not run test releases on my main machine.

Going forward, with data integrity the utmost priority, Steve will be extra extra cautious, doing extra extra testing, consuming extra extra time, to produce a safe test release. And so we will wait "extra extra" for the next test release. I believe it will be worth it.

Bottom line: There will always be risk. Perfection does not exist.
Sometimes if I have a 'bad feeling' about running new software I image my machine first. That way worse case I just loose the time it takes for a restore. Backups, backups, and backups air-gapped, the 3 Bs of computers
We can have it fast, or we can have it good.
I saw a sign in a print shop (before we could all do most of our own printing). It said you could have your work good, fast, or cheap. PICK TWO. So, good and fast but not cheap, good and cheap but not fast, or cheap and fast but not good. Lots of truth in that. Also, @Steve is one developer, not a corporate team. And all the time consuming stuff mentioned here. So, we get the product when we get it. Reminds me of an old wine commercial "we will make no wine before its time ...".

In answer to the OP's question about verifying a drive: Backing up the drive, as stated, is a good idea. Assuming you're running Windows, do a chkdisk with autofix turned off and verify sectors turned on. This does a read verify on all sectors. If you format the drive, turn off quick format and do a full format. Quick format only writes FAT (or modern equivalent) and enough structure to access the sectors. I believe full format fills the drive with zeros. You could also fill the drive with random gibberish data and then do the chkdisk sector verify, etc. There are Linux commands that will make files of gibberish. I have some 8GB, 4GB, 2GB, 1GB, 512 MB, 256 MB, 128 MB, 64 MB, 32 MB, 16 MB, 8 MB, 4 MB, 2 MB, and 1 MB junk files sitting around for testing, etc. All these can fit on a modest memory stick.

ALSO, when I'm burning in a new drive, I fill it with gibberish then run Spinrite Level 4 on it once or twice. YES even an SSD. I'll sacrifice two drive writes to know it's fully functional and tested. But, even if you cannot run Spinrite on it, you can do the above tests. If the new drive is SSD, depends on your budget at 4 TB as they get expensive, set up 10% overprovisioning after doing your tests. You'll have to erase the gibberish data and empty trash to use the drive or just reformat again. Make sure you do all this on a USB 3 computer port or it will take forever.

May your bits be stable and your interfaces be fast. :cool: Ron
Of course! There is nothing wrong with knowing the competition and keeping abreast of it.

Great. I purchased HD Sentinel from https://www.hdsentinel.com. It works under Windows and monitors harddisks and SSDs in the background via SMART and temperature sensors. It has several surface test and sector repair options. Read and write tests, destructive and non destructive. Including an option to refresh the disk surface. (Reads + rewrites all sectors)

Various test options
HD Sentinel test repair options.jpg

Disk refresh currently working on my brand new external HDD
HDSentinel test.jpg

What it lacks in comparison to SpinRite is the DynaStat data recovery system. Spinrite will really do it's best to read a bad sector and recover data from it. So HD Sentinel is more a diagnostic and maintenance tool where Spinrite has better options for data recovery.

I sent the owner a small feedback which he published:
Nice piece of software. I got a read error on my external Hitachi Touro Pro USB harddisk. Hitachi's own drive fitness test still thinks the drive is fine but your software correctly warns that HDD life is poor and that there are many weak and relocated sectors. So I'm not gambling and I safely transferred all data to a new external drive. With all data safe I'm using your software now to Reinitialize the disk surface. Quite a bit of functionality, both to warn, diagnose, repair and maintain disks.
Definitely worth the money.

I paid EUR 36,26 for a lifetime family licence (5 computers pro license) It repaired all the weak sectors of my Touro but even tho the surface is all green now I'm not trusting it anymore. All data is safely transferred to a new HDD which has a 100% drive health. (Touro got 9% before and 15% after repair)

I'll leave HD sentinel as standby tool to monitor the SMART health and temperatures of my drives.
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I agree with using up a few write cycles to verify solid state devices, especially flash drives. With rare exception you can see Spinrite struggling to write quite a few sectors even on a new flash drive. The real time activity screen is handy for seeing that, or watching the estimated time to completion going up instead of down. Apparently manufacturers are of the errors and allow quite a few retries as acceptable, but performance suffers as a result.
Spinrite struggling to write quite a few sectors even on a new flash drive
More likely what you're seeing is that the controller on the drive cannot perform magic. The drive has internal RAM and writes take more time than reads. If you fill up the RAM with pending requests, the drive is going to appear to stall while it catches up. The drive also gets HOT during writes and while heat is considered helpful for the flash chips, it most certainly is not beneficial for the controller chip(s).

If you bought a brand name drive, it was already well tested at the factory and you're most likely not going to achieve a better test than the factory test. While spinning media can take some damaging abuse in shipping to the end customer, and can suffer vibration damage while in use, a solid state device has no moving parts to dislodge, wear or vibrate.
Long ago I bought a couple cheap flash drives that failed not long after I put them in use. Cheap drives are a waste of money and a ticking time bomb in my opinion. As an odd coincidence I had 2 of my flash drives fail in the past week or two. One was a Samsung 256GB flash drive. It isn't recognized at all when plugged in. What I noticed was the USB C connector is moving in and out of the case just a little bit and doesn't have that little 'click' of it making connection in the port. I may try to pull the connector out and crazy glue it in place to see what happens.

The second flash drive that failed is Samsung bar 256GB. I was copying a few GB into it and it suddenly failed. Now when I plug it in Windows says it is a failed USB device. It no longer appears in disk manager and diskpart does not list it. I tried readspeed and it doesn't see the drive either. I am not giving up on Samsung, I actually like them. I've used the heck out of those 2 so it was only a matter of time before they failed, like any other eventually would. No data was lost- backups to the rescue.