Deal alert! 16G micro sd card $5.95, Class 10

[ssfc72]

I was in Staples, just now, in Lindsay and they had some more of their generic micro sd cards, back in stock. :-)
I picked up another 2 cards. :-)

Update - As of Thur eve, only qty 4, remaining.

[fox]

Any idea of speed?

[ssfc72]

Class 10 would dictate what the speed would be. Should be quite good.
Nothing, otherwise on the packaging, about the speed.  I could try and transfer a file, to see what transfer speed is reported.

[fox]

I read somewhere that Class 10 means little with regard to speed. In fact, when I pulled down a review of SD cards on the Rpi, all the cards were Class 10 but there were big differences in their read and write performance (most marked with random data).

[Jason]

If I understand it correctly, classes represent a *minimum* speed. That means there can still be variations in speed amongst a class but the slowest of a class will never be below a certain speed.

https://www.sdcard.org/developers/overview/speed_class/

[ssfc72]

According to that article, Class 10 is good for a minimum sequential write speed of 10 MB/sec.

A UHS 3 sd card is good for a minimum 30 MB/sec.

Note:  for some devices, such as cameras and camcorders, you have to make sure the device says it can recognize the higher UHS standard. Otherwise, the UHS card should work in the device but only at a Class 10 speed!

[ssfc72]

I just did a speed test of copying a 1.2G NOOBS zip file to the Staples,Generic (Gigastone Corporation/Dane Elec Corp, made in Taiwan) Class 10 micro sd card and an Ultra SanDisk, Class 10 micro sd card.
The Staples Generic sd card is 16GB and the SanDisk sd card is 32 GB.

The NOOBS file downloaded to both cards at around the same speed, as reported during the download operation.

The download initially started at around 70 MB/s for both cards and gradually decreased, during the download, to a speed of around 26 MB/s,for the Staples Generic and 32 MB/s for the Sandisk, near the end of the download.

So the Staples Generic card appears to have quite a good speed, for a Class 10 sd card.

[fox]

The problem with your testing protocol is that it doesn't reflect how well your card will operate on a Raspberry pi, at least assuming that the numbers you are reporting are indeed MB/sec and not mbps. Also, this is the most optimal situation you can get. The testing I saw for other cards (here) top out at under 35 MB/sec sequential read and write, and much lower for random reads and writes. And all but the very best cards give speeds of less than 20 MB/sec for sequential operations. When I moved OSes from SD card to usb drive, I got speeds varying from 2-6 MB/sec, declining over time as the operation proceeds. These are, of course, limited by the capacity of usb 2 on the pi.

You never know who makes these generic cards; they could in fact by made by one of the manufacturers of the better cards. If you really want to test your generic SD card against other brands, you can use the method shown here; this link also includes updated results for the pi3. Both this and the other site I highlighted show that Samsung EVO brand cards give some of the best results for non-high price cards, and the Sandisk Ultra card I bought for $15 gives much better random write results than the Kingston I picked up for about $7. In any case, I found that running a full distro (Debian Jessie Pixel or Ubuntu Mate, vs Open or LibreELEC) was markedly faster on a usb HD or pendrive than from an SD card. Starting up apps from the SD card was painfully slow at times.

[ssfc72]

Good info, Mike!  However!

The test that I did on the 2 sd cards I had, was just a "basic" examination of the speed comparison between the cards. One card being a name brand and the other being a Generic (I did note in my previous post that the Generic appears to be a Gigastone/Dane brand, which are somewhat Brand name manufacturers)

I think the test gives an "indication" that the 2 cards are "likely" similar in speeds for other forms of tests, such a sequential read writes, etc.
And yes, during my download speed tests, Mint 18 was showing MB/s speeds and not Mb/s.

Note also that my original post is just about the speed comparison of 2 sd cards and not about their speed, when used on a Raspberry Pi.

For use as a Class 10 memory device in a notebook computer or other device, it looks to me that the Staples Generic sd card compares favourably in speed, to a name brand sd card.

[fox]

Sorry about the pi assumption, Bill; I've had "pi" on the brain for the last two weeks and wrongly assumed that the relevance of this thread was the purchase for booting up a pi. With regard to the "basic test" being representative of other tests, I can't speak for its use in a computer or camera, but for a pi, those links I posted will show that two cards having similar sequential speeds don't necessarily perform similarly with random reads or writes. I also don't know which tests are most relevant for real world scenarios. In my case, the scenario is the use of the card for boot up and to run everything in the operating system.

One of my cards is a Sandisk Ultra as well. While the pi tests suggest that it performs similarly to the Kingston card for everything but random writes, my impression is that it seems faster. If I was using the card in a camera, I would just buy the cheapest reliable model available and not worry about speed at all.