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Newbie
Posts: 3
Registered: ‎06-08-2016

Re: Sandisk Extreme 64GB - Slower write speeds after system format

[ Edited ]

@moogle

 

>>Using SecureErase in PartedMagic has restored it back to normal

 

when you said "it is back to normal" by using SE/PM, I'd like to ask you 2 questions on top of this:

  1. are you confirming the read/write speeds are back to the from factory speeds (up to 190 writting/up to 245 reading)?
  2. if yes #1,  what format have you choosen for to get them back (e.g. fat32, extfat, other)?

Thanks, 

Newbie
Posts: 2
Registered: ‎08-07-2015

Re: Sandisk Extreme 64GB - Slower write speeds after system format


@zakear wrote:

@moogle

 

>>Using SecureErase in PartedMagic has restored it back to normal

 

when you said "it is back to normal" by using SE/PM, I'd like to ask you 2 questions on top of this:

  1. are you confirming the read/write speeds are back to the from factory speeds (up to 190 writting/up to 245 reading)?
  2. if yes #1,  what format have you choosen for to get them back (e.g. fat32, extfat, other)?

Thanks, 


Hi zakear,

 

1. Yes, I used CrystalDiskMark to test read and write speeds on two different 64GB drives. One was formatted to NTFS and the other was left as exFAT like when it came from the factory. The speeds were roughly about 32-34 MB/s read and 12-15 MB/s write on the sequential parts of the benchmark. Both drives were performing similarly poor after having been used for a year and filled up many times.

 

2. After the SecureErase (I booted to linux and used hdparm instead of the gui tool as I couldn't see my flash drive. See this page https://blog.oxplot.com/make-usb-flash-write-fast-again/ on what commands to use.) the drive no longer has a filesystem so I formatted it back to NTFS 4K cluster size using Windows 10.

 

I went and performed the CrystalDisk benchmark and speeds were back up to around 211 MB/s read and 139 MB/s write which seemed back to normal speeds.

 

I also tried copying a large file to the drive before and after secureerase in Windows 10 and before I was getting around 3-5MB/s write speeds, afterwards the drive was copying at around 95MB/s for about 10 mins (the time it took the transfer to complete) which seemed about right as I was copying from HDD -> Sandisk drive.

 

The drive was hot afterwards but back and performing normally. All these posts about ruining the factory partition/sector size is just rubbish. The drive uses SSD flash chips but I don't think there is a controller embedded inside to automatically perform TRIM commands or do wear levelling, which is why the drive will slow down over time with use.

 

Maybe a majority of users who rarely use the drive to copy large files won't see an issue, but if you use the drive too much it will slow down significantly.

 

Newbie
Posts: 1
Registered: ‎07-12-2016

Re: Sandisk Extreme 64GB - Slower write speeds after system format

Hi ! 

 

I've just formated my drive with the Windows tool in exFat (see screenshot below) and I got the same speed as you.

 

2.jpg

 

1.jpg

Newbie
Posts: 2
Registered: ‎04-05-2016

Re: Sandisk Extreme 64GB - Slower write speeds after system format


moogle wrote:


2. After the SecureErase (I booted to linux and used hdparm instead of the gui tool as I couldn't see my flash drive. See this page https://blog.oxplot.com/make-usb-flash-write-fast-again/ on what commands to use.) the drive no longer has a filesystem so I formatted it back to NTFS 4K cluster size using Windows 10.

 

Its abit overcomplicated, why u use linux commands when u already secure erased your drive with partedmagic?
I did a secure erase with parted magic like you too, after that i formated my stick with SDFormatter with these options.

Format Type: Quick

Format Size Adjustment: On

 

Thats it my speed went up again.

 

The good thing about SDFormatter is he sets the correct alignment automaticly, u can check that with AS SSD Benchmark tool (see screenshot) if there is ok you are good, if there is BAD you are i guess u know it Smiley Very Happy

so i think the stick loses speed if there is a wrong alignment.

 

speed.jpg

 

speed2.jpg

 

ITK
Newbie
Posts: 1
Registered: ‎07-24-2018

Re: Sandisk Extreme 64GB - Slower write speeds after system format

Just wanted to let you guys know that secure delete via "hdparm" worked fine for me on Linux.

 

  1. hdparm --user-master u --security-set-pass Nine /dev/X   <- Enable drive security
  2. hdparm -I /dev/X   <- Check if security is enabled
  3. hdparm --security-erase Nine /dev/X   <- Worked for me without --user-master u,  this will wipe all data in less than 30 sec
  4. hdparm -I /dev/X   <- Verify that security is disabled

dev/X = drive name, for example /dev/sdg

 

My speeds went from 10MB / sec to over 200MB / sec again Smiley Happy

 

Best regards,

IT-Technik Klimt

SanDisk Guru
Posts: 2,812
Registered: ‎07-23-2010

Re: Sandisk Extreme 64GB - Slower write speeds after system format

But don't you then have to format the drive?  And for 64GB as exFAT?

Ed
Important files = Backed up files
Newbie
Posts: 1
Registered: ‎08-14-2018

Re: Sandisk Extreme 64GB - Slower write speeds after system format

[ Edited ]

Just off the phone with Sandisk support. Their USB sticks and memory cards are ment to be formatted. 
So, format them if you want for as much as you want. You won't break it by doing so. 

 

Just like SSDs, no way you can physically break your USB disk or have it's performance degraded by formatting it (however obviously you will loose data on it). Well, not as long as you format it 24/7 for a couple of years (wear out memory chips by writing data more times than it's been designed to handle; and those are pretty generous nowadays anyways). 

 

So happy formatting, people!

If the drive performs slowly (or does not work at all) then you should contact the support.

dnk
Newbie
Posts: 1
Registered: ‎12-13-2018

Re: Sandisk Extreme 64GB - Slower write speeds after system format

I made secure eraze in Disk Utility on mac os with exFat option and 1 Security (it was about 1 hour) level and it works back fast as new!

Newbie
Posts: 2
Registered: ‎02-22-2019

Re: Sandisk Extreme 64GB - Slower write speeds after system format

[ Edited ]

Hi,

 

I just came accros this topic and want to add my findings.

 

I bought a SANDISK Cruzer Ultra Flair 3.0 128 GB, which didn't let me copy files larger then 4Gb. (on windows and linux)

Trying to find an solution I read about the three file systems and their differences: Fat32, exFat and NTSF.

Two different windows computers showed that the usb-stick was formatted as exFAT.

 

As a test I tried to copy an .iso file from 4.7Gb to the stick. All attemps failed, a message stated:  the file is too large.

Then I  re-formatted (slow) the stick in a windows computer to exFAT.

After that I was able to copy the 4.7Gb .iso file to the usb-stick.

 

It looks like as if Sandisk  is using a modified exFAT  file system, perhaps to support their SanDiskSecureAccess environment.

(as a result, customers are not able to share easily  (high resolution holiday Cat Wink) movies among each other)

It would be nice to know if it  is a modified exFAT file sytem or not.

 

SanDisk Guru
Posts: 2,812
Registered: ‎07-23-2010

Re: Sandisk Extreme 64GB - Slower write speeds after system format

HIGHly unlikely it was a modified exFAT file system.  A counterfeit drive, maybe.

Ed
Important files = Backed up files