Flash Drive vs SD Card in Reliability

[easysurfer]

I know brand probably matters also, but in general what's more reliable a flash drive (thumb drive) or SD card?

I've killed a SD card in the past unplugging too quickly but also have had a flash drive unreliable so had to toss.

My use is for read/write storage of important information. Currently using a re-writeable CD but in comparisons, the time takes forever vs flash or SD.

 

[SecondCor521]

I agree that brand matters.

Both types of storage use the same underlying memory technology (NAND flash) so there is no difference there. Mechanically there are also no moving parts in either technology, so no difference there either.

There are a couple of ways either of them could fail:

Hot plug or removal of the device during a data transfer. Probably more dangerous on a write of data vs. a read of data. The risk here is small though, as the device manufacturers know about this use case and design the device to handle it in 99.999% of cases.

Wearing out of the underlying NAND. NAND memory can only be written a certain number of times before it fails. The device manufacturers know this and design around it as best they can, but if you read the fine print the device is only waranteed to store data for a certain number of terabytes - past that point it is possible for the underlying memory to wear out so much that it just can't hold data any more. With average use, this will be many years, but if you're an extremely heavy user over a long number of years (5-10), you could see it.

Bad firmware or hardware. This is where the manufacturer comes in. There is actually a fair amount of firmware/hardware that manages the memory itself and the data transfers (and the blinky light on your USB stick if it has one), and sometimes there are defects here. Happens to everyone in the industry, but less often to the higher reputation manufacturers. Personally I would trust Micron and Samsung and Toshiba, but would stay away from Sony and Kingston and any other off-brand names.

There are other failure modes but they are much less common.

If you're storing important information on them, I would make certain that you have a good backup system in place (cloud, another drive, whatever).

https://superuser.com/questions/594357/ssd-sd-emmc-raw-nand-what-are-the-differences

 

[easysurfer]

Not storing a whole lot, but stuff like some pass codes and phone QR codes that I don't want sitting on my computer in case falls in wrong hands.

Thinking about this more, know what I'll do.

I'm going to use both a SD card and CD-RW disc as backup.

The SD card for faster updates, but still a burn to CD-RW as backup in case the SD card fails.

 

[braumeister]

They're not expensive, so get the fastest ones you can and make multiple copies.

 

[OldShooter]

... I've killed a SD card in the past unplugging ...

Almost certainly the card would have been fine if you reformatted it.

The issue with unplugging before you "eject" the card is that the computer may be in the middle of writing data to the card and that write is interrupted, corrupting the data.

One of the things the operating system typically does is called "write caching." When data on the card is changed by the user, the change is actually made to a copy of the data that is kept in the computer's fast memory. After a certain amount of time or a number of changes, the data is written to the card or flash drive. This "lazy write" speeds things up because reading and writing to the computer memory is much faster than actually writing to the card every time. But .... if the write is incomplete and you pull the card, there will almost certainly be trouble. When the user commands an "eject" that causes the operating system to flush the write buffer onto the flash drive or SD card. Only after the write is complete is the user told that it is safe to remove the device.

 

[Red Badger]

I've used Google cloud storage since 2014 without any issues. Might be a reasonable BU option if your portable device crashes.

 

[easysurfer]

Almost certainly the card would have been fine if you reformatted it.

The issue with unplugging before you "eject" the card is that the computer may be in the middle of writing data to the card and that write is interrupted, corrupting the data.

One of the things the operating system typically does is called "write caching." When data on the card is changed by the user, the change is actually made to a copy of the data that is kept in the computer's fast memory. After a certain amount of time or a number of changes, the data is written to the card or flash drive. This "lazy write" speeds things up because reading and writing to the computer memory is much faster than actually writing to the card every time. But .... if the write is incomplete and you pull the card, there will almost certainly be trouble. When the user commands an "eject" that causes the operating system to flush the write buffer onto the flash drive or SD card. Only after the write is complete is the user told that it is safe to remove the device.

When I killed the SD card, either the computer was slow and didn't respond or I was too fast in the draw and removed too early.

The computer had the SD reader built-in. When I use my external reader, after the dismounting, I pull from the USB connection to be save and not the card itself.

 

[Car-Guy]

Never had either a SD card or USB fail. However, for important stuff that I keep on a USB, I'll simply use two USB sticks and make a copy. (they are dirt cheap now-a-days.) I still have my first USB stick that's probably more than 15 years old now and it sill works. Although the limited capacity of that particular stick isn't worth using by today's standards.

 

[easysurfer]

Okay. I ended up using an my first flash drive (256 MB, purchased for about $60 at Best Buy years ago) instead of the CD-RW disc. So, I'll use the flash drive and a SD card I had extra, laying around.

256 MB is plenty of space for what I'm doing .

 

[RetiredGypsy]

In reliability, you're looking at the same issues across both. The slow leakage of electrons means they'll lose data after X number of years, fewer or more depending on storage environment. The odds of reaching its limit of writing data over and over again is going to be rare.

As far as brand goes, it seems like they all have about the same level of consumer reliability (SanDisk, SeaGate, Western Digital, HGST, etc).

It's good practice for archiving digital media to be backed up every couple of years anyway (HDD, SSD, flash, SD, whatever).

 

[Jerry1]

Thinking about this more, know what I'll do.

I'm going to use both a SD card and CD-RW disc as backup.

The SD card for faster updates, but still a burn to CD-RW as backup in case the SD card fails.

I have had way more issues with trying to read old CD's and DVD's that I've written to than any other media. I back up my files on small portable hard drives like a Seagate back up drive (about $70 for 1TB of storage). I get two of them and double back up my data.

I've never had a problem with a flash drive or memory card. If I had a small amount of data, I'd get a couple cheap ones and double back up using those. Fast, compact and cost is becoming very reasonable. A quick look shows a SanDisk 16GB USB 3.0 for $9. The 128GB is only $30.

 

[savory]

SIL who is highly security minded suggested the Kingston thumb drive for performance and security. I back it up with a regular thumb drive which I change out regularly.

I use -

DataTraveler Locker+ G3
Secures personal data with hardware encryption and password protection
Automatic USBtoCloud™ by ClevX™ backup option to access your data anytime, anywhere
Fast USB 3.0 interface
Works with both Windows and Mac
Easy to set up and use
Durable metal casing with key loop

I do not use their cloud feature as I prefer access to this personal data to be offline.


DataTraveler Locker+ G3 USB - 8GB-128GB | Kingston

 

[OldShooter]

... When I use my external reader, after the dismounting, I pull from the USB connection to be save and not the card itself.

That won't make any difference. The issue is a lazy write getting interrupted. Breaking the USB connection is the same as pulling the card. Just be sure to "eject" the SD card and don't pull it until the OS tells you it is safe to do so.

 

[ERD50]

I agree that brand matters.

Both types of storage use the same underlying memory technology (NAND flash) so there is no difference there. Mechanically there are also no moving parts in either technology, so no difference there either. ....

If you're storing important information on them, I would make certain that you have a good backup system in place (cloud, another drive, whatever).

...

My experience is that even the cheapest off-brand flash drive or SD card is very, very reliable, even if it less reliable than name brand.

But any storage can go bad, so you need a backup anyway, and these devices are so cheap now, there is no reason to not have multiple back ups.

With multiple back ups, the odds of three devices/cloud going bad at the same time are practically nil. Just do it.

-ERD50

 

[target2019]

That won't make any difference. The issue is a lazy write getting interrupted. Breaking the USB connection is the same as pulling the card. Just be sure to "eject" the SD card and don't pull it until the OS tells you it is safe to do so.

One guess is that an SD card may be more sensitive to ESD than a USB device. This would be at the moment you touch it, and then pull it out. Just a guess.

 

[kcowan]

I have 2 WD USB drives one for everything (750 mb) and one (250mb) for the weekly transfer of active storage from documents.

 

[W2R]

I never had any problems with either.

I have four thumb drives and use them all the time. I carry one with me at all times.

I do a weekly backup on one of my thumb drives and copy it to my external hard drive. Like ERD50, I think storing multiple copies of anything important on multiple devices is the way to go.

I only have a few SD cards (from my video game consoles, storing my game play/progress) but have had no problems with them either.

I don't store things in the cloud because I am a crotchety old lady who is a bit of a control freak about the files I store.

 

[Lawrencewendall]

Just be careful. There was a rash of bogus Kingston USBs being sold cheap on eBay a while back. They weren't really bogus but their components would not pass quality control and trashed. Frugal workers were pulling them out of the trash and selling them. Don't recall what models.

 

[W2R]

These days, thumb drives are so cheap that I see no reason to buy them from dubious sources. You can get a 32 GB Kingston thumb drive, from Kingston and sold by Amazon, for $11.99.

I love it. I can remember long ago when I paid more than that for a 1 GB thumb drive (which I still have).

 

[easysurfer]

I managed find an old 16 GB thumb drive. So I decided to use two thumb drives. No need to use a SD card or CD-RW.

 

[AutumnElf]

Brand is important. You're asking for trouble buying those cheap off-brands. They don't last long and shouldn't be trusted with something as important as your data.

So far I've never had either fail me. Neither has moving parts, so this helps the longevity your data as opposed to say, a spinning hard drive. But either could definitely fail if you pull before data is written, during a brownout, etc. Don't leave them sit in the computer. Be patient and make sure data is written before pulling them. And keep them stored in cool places.

 

[Rustic23]

I vote for google drive! They give you 15G of storage, and you only want 256 meg or less! They have a new feature that sync's your folders automatically. I think it is too new for any reviews. I am in the process of putting DW's pictures on it. There are 8,000 files! It is going to take awhile.

 

[mountainsoft]

The key to backups is redundancy. ALL media will fail at some point, so it is important to have multiple backup copies, regardless of which media type you choose.

On a dollar per megabyte basis, it's hard to beat hard drives. They're fast, inexpensive, and can store large amount of data. I personally backup to an external 3TB external hard drive every night. Once a month I swap that drive with a second drive I keep in the safe deposit box at the bank. If I should have a house fire or other major disaster that takes out my main computer and my backup, I still have the backup at the bank to recover files from.

However, the main issue with hard drives AND flash drives is that they are rewriteable. If the data on your main hard drive is corrupted due to a virus, drive failure, etc., you may copy that corrupted data to your backup drive without realizing it. In effect, you overwrite your good backup data with corrupted data.

For that reason, I also backup my hard drive to Blu-Ray discs every few months. As these are write-once media, I know that they won't be overwritten with possibly corrupted data later on. Of course, optical media like CD's, DVD's, and Blu-Rays degrade over time so I do not rely on them as my sole backup.

Again, it's all about having multiple copies of your data on a variety of media.