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Anonymous
(Unregistered)Tue 14-Feb-12 15:16:46
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SD cards speeds


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I have recently returned a class 10 micro card because it was not compatible with my system. How is one to know what speed to buy. I assumed that the highest speed will be backward compatible. I bought one for Tablet. My xp win computer say that no space on the card despite the fact it is a blank 32 gig. So I am going back to class 4 which is much slower.
Standard User TMCR
(regular) Tue 14-Feb-12 15:22:19
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Re: SD cards speeds


[re: Anonymous] [link to this post]
 
It may not be the speed, but the capacity which is not suited.

I bought some 8Gb SD cards for a camera, they didn't work. Then I read in the camera instructions that the maximum size was only 2Gb.

That sort of thing may be worth looking at ?

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Anonymous
(Unregistered)Tue 14-Feb-12 16:12:12
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Re: SD cards speeds


[re: Anonymous] [link to this post]
 
SDSC cards above 1 GB





4 GB SDSC card
A host device can ask any inserted SD card for its 128-bit identification string (the Card-Specific Data or CSD). In standard-capacity cards (SDSC), 12 bits identify the number of memory clusters (ranging from 1 to 4,096) and 3 bits identify the number of blocks per cluster (which decode to 4, 8, 16, 32, 64, 128, 256, or 512 blocks per cluster). The host device multiplies these figures (as shown in the following section) with the number of bytes per block to determine the card's capacity in bytes.

In SD version 1.00, the number of bytes per block was assumed to be 512. This permitted SDSC cards up to 4,096 512 512 = 1 GB, for which there are no known incompatibilities.

Version 1.01 let an SDSC card use a 4-bit field to indicate 1,024 or 2,048 bytes per block instead.[39] Doing so enabled cards with 2 GB and 4 GB capacity.

Early SDSC host devices that assume 512-byte blocks therefore will not fully support the insertion of 2 GB or 4 GB cards. In some cases, the host device can read data that happens to reside in the first 1 GB of the card. If the assumption is made in the driver software, success may differ from one version of Windows to another. In addition, any host device might not support a 4 GB SDSC card, since the specification lets it assume that 2 GB is the maximum for these cards


http://en.wikipedia.org/wiki/Sd_card#SDHC

I bought a 8Mb, ok not half a dozen photos now or not even that on a new camera but in 2000 so 12 years ago that is what was going for over £35. camera camera came with a 4mb one and with the less than 1mega pixel camera did a good 24 shots. Bought the 8mb ( I know rubbish museum piece now) and diid not go, read instructions and it went up to 4Mb cards so would agree with that.

http://en.wikipedia.org/wiki/SmartMedia so dear in their day

Google the thing you are trying to use it in and get specs or furums up somewhere.

Might take a slower card but my money would be on the size was to big.

Might have been worth trying in someones new digital camera at the workplace.
Friends with the neighbours. Might have been a duff card that whatever you tried like formatting or whatever it was put in was not going to go. with my new camera I got last September, got a 16Gb card off of ebay for about £16... double that price 12 years ago for 2000 less srorage space!.
to the point, that did not go, got a replacement quickly as the seller was good and did and all ok.

Find out what the item you have in mind can take.

loks like both off us here have been caught out with to big cards so no good (ok mine was 12 years ago but still true now), read the new camera takes a size and no more so bought what I knew was ok.


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Standard User Dick_B
(regular) Tue 14-Feb-12 16:41:23
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Re: SD cards speeds


[re: Anonymous] [link to this post]
 
If you are using PC/Laptop slot to read the card it is most likely the capacity/card type that is the problem. At 32GB it will be SDHC which needs an SDHC or SDXC (even bigger) reader. These are available quite cheaply on the web. I have not experienced problems with a card that has a speed rating greater than required but you may get problems with a card that can not reach the speed of the device it is being used in.
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