Dollar Store USB Sticks - Page 1
Forum section: electronics / general

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 04, 2023, 01:07:19 am
content: I was at a Dollarama just recently getting some sharpie pens when I checked out their gadgets and noticed there was a 32GB stick for $5. Taking it home, I quickly noticed I had binary diff errors that cropped up in writes of like 3GB. And a good number of problems. So at first I tried to use badblocks in linux and I was going to try to make partitions around hopefully a few failed areas, and badblocks said they were pretty much everywhere. I took the stick apart hoping there was bridges or cold joints somewhere. The flash was a BGA so I can't deal with that. What I did see was a lot of gluegun mess on the PCB as well as a hair that would be longshot being a metal filament. I removed those and so far it is working properly and at this moment I passed diff of around 10GB. Does anyone expect glue gun glue to tip the scale? Maybe a bad joint is working again for a while? Must be that damn R2.

author: eti
author_rank: Super Contributor
timestamp: March 04, 2023, 01:12:53 am
content: $5 may be "only $5" but would you buy a cheeseburger with flies all over it? You've still wasted $5. I am never sure why people are tempted by "deals" like this. Pay proper money for a brand name when your data relies on it.If it's "32GB" then that's a reasonable amount of space for me to presume you were considering storing a fair amount of data on it. The ONLY sane question could be "why bother?"I have a friend who constantly buys "bargains" and cheap crap like this - why do people not see that all these small amounts soon add up? Bin it, and don't buy any more junk again... ok? End of lesson

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 04, 2023, 01:25:33 am
content: Here is the reverse side. It has now passed 25Gigs of binary difff. I mean there is 25 gigs of stuff on the stick right now. I think it is like a multi package pcb so you can put in a bga or a flatpack. OK JUST IN I DID GET PROBLEMS AGAIN so oh well. I just used some isopropyl and there may be a cold solder on the usb connector that I may investigate may be dipping the rails. I just resoldered where the usb port connects to the pcb, This is my last try and then I am shelfing it.

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 04, 2023, 06:12:09 am
content: That's it I give up on it. It does not seem to be reliable for whatever reason.

author: wraper
author_rank: Unknown
timestamp: March 04, 2023, 06:33:41 am
content: Why do even bother to buy USB2 Flash drive. It's so slow it's pain to use. Also it's not a bargain, similar garbage class 32GB drive from reputable brand can be bought for less.

author: newbrain
author_rank: Super Contributor
timestamp: March 04, 2023, 02:56:19 pm
content: Quote from: eti on March 04, 2023, 01:12:53 amCall me an ambulance, I am agreeing with eti

author: shapirus
author_rank: Super Contributor
timestamp: March 04, 2023, 03:15:10 pm
content: Quote from: eti on March 04, 2023, 01:12:53 amUnfortunately, this still doesn't guarantee anything. Even brand name storage sticks are very often of crappy quality.And even with good quality ones, one should never rely on them to be able to read data back. And it's not limited to USB flash storage. Any storage can fail at any time. This is why backups are vital. This is also why it makes more sense to spend more on multiple separate devices of different brands and types (and spending time and effort to set up automated scheduled backups) rather than spend more on a single device hoping to achieve higher reliability.

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 05, 2023, 02:56:17 am
content: Weird thing is there is some kind of factory software you can get for it and so far I just made it messed up and it says media ejected capacity zero now. But it is interesting.

author: amyk
author_rank: Super Contributor
timestamp: March 05, 2023, 05:16:33 am
content: That's Intel/Micron B27A TLC, interestingly enough a 512Gb (64GB) part, either severely underprovisioned perhaps due to many bad blocks, or being used as MLC instead of TLC.

author: MrMobodies
author_rank: Super Contributor
timestamp: March 05, 2023, 05:19:12 am
content: For a little play and experiment then I'd see it as a bit of fun but when put to use and depended on I find that the aggravation isn't worth it.

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 05, 2023, 06:44:13 am
content: I think if you scan instead of just clear and a few other options is basically works. I tried to change a few options but I get the feeling I did not do a relocate sort of scan. I am going to see if it changed anything. Oops I put a capital A in there. Oh well. I have a windows 7 vm in linux. I copied the .qcow or whatever to a new one and made a new machine with the copy. Then I put in that stuff that was sort of dubious and disabled the network so it could not do anything to my actual computer. When I run the VM I split up a lot of the hardware to the VM instead of the main computer, so the ports were directly interfaced to Windows 7. Well just got a diff error on 6GB of writes.

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 06, 2023, 11:21:14 pm
content: I came up with an approach to make it worth something to me. I used the factory scan that I think differs from the stand scan in that it does not de allocate block. The theory is like this.1) I see there is this ECC level, which was 12 of 15. I take that as an attempt to get good data out of the bits of the flash regardless if they are all working or not.2) I would say sporadic failures occur with certain data in certain offsets in the memory that was not in its initial bad sectors list as per using ECC.3) I argue if I can set ECC level zero that would eliminate any correction, and do a disk scan with patterns I can find the bas sectors.4) Through software, granted certain critical areas are ok like the MBR block, I can make an exclusion map using ext4 for example.I just did one test and my initial 3+Gb write diffed ok. So if this is the case I would say that the basic technology was reliable, but it was implemented in a non reliable manner. It could be the technology is fundamentally unreliable. NOPE second try produced lots of errors.****ok a few hours later. Well I noticed a few things. One is it will accept pretty much anything I want it to do if I clear the stick and then re install it before doing it. The last setting I wanted to see if I altered 'r/w' cycle to 66ns, that is to say try to slow down a process. I left ecc zero. What happened and it was rather odd was the first 3 Gugs again verified (without any bad block declaration). So I am still testing things.****Mar 7 - Still have not found a reliable configuration. It works for a while and then totally messes up, so I guess that is the way this stuff just is.

author: niconiconi
author_rank: Frequent Contributor
timestamp: March 09, 2023, 07:45:39 pm
content: Cheap USB flash drives are where all the bad NAND flash chips of the world went to...

author: msuffidy
author_rank: Frequent Contributor
timestamp: March 10, 2023, 12:03:59 am
content: Well I think the point here is I TRIED to get a dollar store USB stick thinking it would be slow but may be data safe. That was not the case. I did a last ditch reflow in my literal oven and it started to melt the solder, but it was never really flowy. I was hoping to fix up bga connections. The reflow (attempt) did not make it reliable, but it still works. I thought I would make a final set of conclusions.1) The idea that I could turn off ECC and do a bad blocks check through software may have been flawed by the fact reading may be compromised by error and thus I did turn the ECC back on.2) My experiments showed that choosing the fastest access time of 25ns with my unit still worked (as well as any slower setting), thus longer accesses are just wasting time.3) My final settings were 25ns r/w cycle, factory scan, ecc level 12.4) I am not even sure the flash has problems because areas that before failed did succeed in getting written to later. The problem may be in the controller.5) What seems to work is to insert the stick and do an filesystem image write to it immediately using dd. I have done a 12GB write and a 4GB write just now doing this (without diff errors). I noticed a pattern of the first writes mostly working as I was experimenting. So for that application at least I can use that method to give movies etc to friends to copy and thus be a use of some sort.