Thursday, 16 June 2016

Very cheap, very fast, very big hard drive?

It suddenly occurred to me that maybe I could make a pseudo hard drive out of a bunch of SD cards. So I went to Ebay.

First, something to put the cards in. You can get an adapter that takes ten SD cards for £15.49

Next, the cards. You can get 512 gb SD cards for £3.99.

So ten cards and the adaptor is £55.39, giving you 5tb of storage. And I'm guessing that it would be faster than a spinning disk. A 5tb hard drive would cost £144 at Aria.

A pair of these would cost £110.78, giving you 10tb for the price of 4tb in hard drives. 8tb drives cost £187.14. Also faster (I think, because physically moving things tend to be slower than electronics), lower power, and (I'm guessing) more reliable. The sales page claims that if you use all ten cards, the read-write speed is 350mb/sec, which is massive. I don't think one would get this in practice.

I've googled for a while, and I can't find anyone who has actually tried this. I've emailed the vendor about the SD cards, because they seem very cheap, and they're pretty new to Ebay. The next lowest price for 512gb cards is £6.27.

I'm tempted. I'm awfully tempted!

... later ...

I think those 512gb cards are fake. I've done a bit of checking around, and it seems that this is a common scam.

Just as well I didn't go for it.

Well, I kind of did. A few days ago, I bought a so-called 512gb card on Ebay. I paid for it, it was dispatched, according to the vendor, but it hasn't arrived yet (it's too soon for that). When it does arrive, I'll give it a thorough test, and if it can't actually store 512gb (I'll copy a log of big files to it) then I'll claim a refund via Ebay.

And I've just had another thought. And I'm now testing the 256gb card I bought recently for £5.59!

... later ...

... which seems to actually be 8gb. The writing on the drive says 256gb, and the drive announces itself as 256gb, but if you try to put more than 8gb on the drive, it announces that it's full.

Which only goes to show, I can also be scammed. The usual rule applies - if something seems too good to be true, then it usually is. The problem with that, is that it isn't always true, I've found many wonderful bargains on Ebay.

The fake memory card problem seems to be rather common.

Now I'll find out if the vendor (they're importing the cards, and they might not realise that they're fake) will refund, and if not, whether Ebay will take action. It's only £5.69, so we won't be starving at Solly Towers, but still.

... later ...

And now I'm doing a write test on the 64gb card that I'm using as the boot drive of my new big 64gb server. If it's going to fail, I'd rather know now, than later. This is a 64gb card that I bought nine months ago for £13.09

... later ...

Phew! That card worked fine, I filled it up to 64gb. But I also have a 64gb USB memory stick, bought a few years ago, which turns out to be 8gb. And that's now got everything tested, except the stuff I buoght in the last few days, which hasn't arrived yet.


  1. Until I read your recent blog about 512GB SDCards I didn't know they existed. I tried to order from, I suspect, the same supplier you initially used, but eBay wouldn't accept Paypal for that order. Instead, I bought a similar one - same pic - from a UK supplier (£14, still cheap I thought). Windows says it has a capacity of 499GB. It was formatted to FAT32, I've reformatted it to NTFS. I'm currently loading a couple of backups onto it to stress it, I'll report back.

  2. Very common scam, especially on eBay. I am surprised you have only now heard about it. The cards (or USB drives) are formatted with faked headers that claim they have much more capacity than they do. Users don't put a lot of data on them right away, or try to read it back, so they think they are working. Sellers even get great reviews based on the price. Then the cards start to deliver corrupted reads and the buyers think they have gone bad.

    The standard tool for testing for false capacity is H2TESTW, free all over the net.

  3. Sorry Nigel, but you should be able to get a refund. Mine hasn't arrived yet, but when it does, I'll give it a test before giving feedback, and if it's fake, I'll ask for a refund.

    My test method is to copy 256 gb of data to the card, and see what happens. What I got was lots of I/O errors, and at 8gb it reported that the card was full.

    Caveat emptor!!!

  4. This has been going on a long time. EBay apparently doesn't try to police it. The vendor will give you a refund without a quibble- only a small percentage of their customers ask for one. If you sift through their feedback, you will find a few, very few, complaints from people who know what is going on, but these are overwhelmed by plaudits from the clueless.

  5. The H2TESTW takes an awfully long time, so I only tested the first 64GB. 6.4GByte was written OK, the rest was all missing. I'll send the test results to the vendor and expect a refund. They're in the UK so will be more careful to protect their reputation so I don't expect any problem.

  6. I tested two more 64gb devices. One passed, one failed. Yes, my 256gb was a UK supplier. I've complained, we'll see what happens.

    What a scam!