Develop Bugs

[Q] MicroSD card...is this a good deal?

Hello people,
I just came across this microsd card deal:
http://mobile.dailysteals.com/Default.aspx
this is samsung 16 gb class 2 micro sd card. But I am not sure if this is a good deal or not? can anyone tell me ?
Thank you,

Class 2 cards are SLOOOOW! I'd much rather spend a few bucks and get a faster one. I wouldn't get anything less than class 6, and usually go for the class 10 cards. Basically, the speed for a class 2 card is 2 MB/s, a class 6 is 6 MB/s, and so on.

bknust said:
Class 2 cards are SLOOOOW! I'd much rather spend a few bucks and get a faster one. I wouldn't get anything less than class 6, and usually go for the class 10 cards. Basically, the speed for a class 2 card is 2 MB/s, a class 6 is 6 MB/s, and so on.
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Yes that is what I read somewhere. Just wanted to confirm. Thanks for helping me out.
Sent from my SAMSUNG-SGH-I897 using XDA App

Classes only apply to minimum write speed, not read speed, which is far more important.

JPS81 said:
Classes only apply to minimum write speed, not read speed, which is far more important.
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Right: a Class 2's and a Class 6's speed-differences will only be apparent when copying files to the SD card from the PC.
Samsung 16GB C2 MicroSD
Subtotal : $14.99
Shipping Charges : $4.99
Total Charges : USD$19.98
Yes, that is a good deal. I paid USD$28 for my Sandisk just yesterday, and that was the best deal I could find (on eBay). Mine did come with a USB-reader, though.

waghoba said:
Yes that is what I read somewhere. Just wanted to confirm. Thanks for helping me out.
Sent from my SAMSUNG-SGH-I897 using XDA App
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Don't be fooled into buying a card on class speed alone - 16gb and 32gb class 6 are very pricey. If you mostly store movies and music on your SD card a class 2 is fine. Even for recording video on the phone, class 2 works fine.
If you are wiping your SD card or filling it with new data all the time, then maybe you want faster write speed - but I would rather save my $$$ for now. The same class 6 cards will be half price in a few months.

alphadog00 said:
Don't be fooled into buying a card on class speed alone - 16gb and 32gb class 6 are very pricey. If you mostly store movies and music on your SD card a class 2 is fine. Even for recording video on the phone, class 2 works fine.
If you are wiping your SD card or filling it with new data all the time, then maybe you want faster write speed - but I would rather save my $$$ for now. The same class 6 cards will be half price in a few months.
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PhrProfess said:
Right: a Class 2's and a Class 6's speed-differences will only be apparent when copying files to the SD card from the PC.
Samsung 16GB C2 MicroSD
Subtotal : $14.99
Shipping Charges : $4.99
Total Charges : USD$19.98
Yes, that is a good deal. I paid USD$28 for my Sandisk just yesterday, and that was the best deal I could find (on eBay). Mine did come with a USB-reader, though.
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Click to collapse
JPS81 said:
Classes only apply to minimum write speed, not read speed, which is far more important.
Click to expand...
Click to collapse
Thank you for all of you for your replies...but unfortunately the deal was gone by the time I decided to buy
Now waiting for next best deal, at least now I know that just for storing music and vids class 2 is fine !

Go over to G1 forum and search this. Not sure what our phone's max read/write speed is but I am sure its similar to HTC devices- Class 6. You can spend the money on the class 10 but its useless for mobile devices.
Also, some say its only for pc -read/write- not 100% true. however, maybe for our particular phone....
For example- on the dream you can use your SDcard as a swap file placing an EXT2/3/4 partition on it. The class 6 has better performance and longer life than a class 2- i dont recall why exactly but you can easily google it. It was something about after so many read/writes it will burn out the SD but there is more technical factors to it. It has to do with bit allocation and spreading the writes over the card as to continual writing to the same spot- IIRC(dont quote me on that I havent thought about this in a looong time). Now, as this pertains to our devices- well it doesnt really since we dont utilize SDCard swap files and such for our devices. So talking in a circle, I guess for our situation it does only relate to PC writes..

^o hai thx

malfuncion said:
Go over to G1 forum and search this. Not sure what our phone's max read/write speed is but I am sure its similar to HTC devices- Class 6. You can spend the money on the class 10 but its useless for mobile devices.
Also, some say its only for pc -read/write- not 100% true. however, maybe for our particular phone....
For example- on the dream you can use your SDcard as a swap file placing an EXT2/3/4 partition on it. The class 6 has better performance and longer life than a class 2- i dont recall why exactly but you can easily google it. It was something about after so many read/writes it will burn out the SD but there is more technical factors to it. It has to do with bit allocation and spreading the writes over the card as to continual writing to the same spot- IIRC(dont quote me on that I havent thought about this in a looong time). Now, as this pertains to our devices- well it doesnt really since we dont utilize SDCard swap files and such for our devices. So talking in a circle, I guess for our situation it does only relate to PC writes..
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Hey that's a lot of technical information, but thanks. Now I understood that the class doesnt really matter. So next time if any good deal is out I will just jump on it.
Sent from my SAMSUNG-SGH-I897 using XDA App

micro SD card

I can't wait to chuck my iPhone for my first Android!
Maybe I'm being too anal here but which micro SD cards will you be using?
Will a Class 10 be significantly faster than lower classes?
How are lesser name brands like Memorette? I'm looking through eBay and these are much cheaper than SanDisk and Lexar.

I prefer sandisk over other brands as had bad experienxe with lexar but its just me.
And yes class 10 would be faster.

...although Class 2 will likely be fine for every purpose in the phone, I'll be testing my Class 2 Sandisk 32GB with mine in my review for Clove's blog.

Got a Joyflash Class 10 16GB got it for less than £18 and speeds exceed over Class 10 on read and write very good for the price.

How does it benchmark? Would be interested to see some crystal disk numbers for it...
I'd tend to advise sticking with Sandisk myself...

NZtechfreak said:
How does it benchmark? Would be interested to see some crystal disk numbers for it...
I'd tend to advise sticking with Sandisk myself...
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This is the one I have: Big thread here:
http://forum.xda-developers.com/showthread.php?t=1000894

Pretty nice benchmarks, although for smaller and random writes the speeds drop off a bit (these are closer to actual in-phone use, with the exception of large sequential read/write things like video recording). The 512k write test is slower than my Sandisk Class 2 card, so its not all peachy, but for the price that looks like a steal - I suppose they don't make 32GB cards?

NZtechfreak said:
Pretty nice benchmarks, although for smaller and random writes the speeds drop off a bit (these are closer to actual in-phone use, with the exception of large sequential read/write things like video recording). The 512k write test is slower than my Sandisk Class 2 card, so its not all peachy, but for the price that looks like a steal - I suppose they don't make 32GB cards?
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Not yet! Would love a bigger card but cost too much ££!

Looks like there is opening for bloggers to test and review microsd cards
Sent from my HTC Hero using XDA App

nikzDHD said:
Got a Joyflash Class 10 16GB got it for less than £18 and speeds exceed over Class 10 on read and write very good for the price.
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That looks sweet but I have no idea how to purchase that as I'm in the U.S. The only ones I see are the 8GB version on Amazon.co.uk and the one from eBay but they don't seem to ship here.
Where else can I purchase one?
Do they even have a 32GB?

I picked up one of these, havent tested it yet but thought it looked a good buy.
http://www.ebuyer.com/product/218439

So does anyone know what class speed is optimal for this phone?
For original galaxy s users, was there a plateau in speed reading/writing after a certain class/

Bought a "ADATA Turbo microSDHC 32GB" (http://geizhals.at/deutschland/a610468.html) and it seems pretty fast. Testet with a kingston usb reader (http://geizhals.at/deutschland/a432624.html).
Don't know if it work with SGSII yet.
View attachment 579619

NZtechfreak said:
...although Class 2 will likely be fine for every purpose in the phone, I'll be testing my Class 2 Sandisk 32GB with mine in my review for Clove's blog.
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Surely Class 2 would be too slow for HD video recording?

AaronUK said:
Surely Class 2 would be too slow for HD video recording?
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Thats the question I want to answer. Its fine for 720p video recording, since I use it in my SGSI right now, whether its still good enough for 1080p is the question. The Class 2 Sandisk writes at 5.5MB/s for sequential writes, which may still be enough for 1080p. Will know soon enough one way or the other.

I'm considering a 32gb Class 4 Sandisk from eBay, but don't really want to buy it until we've worked out if it's going to be suitable. I imagine it'll be fine, but still...

From Ebay? You're sure its genuine? I don't see Class 4 Sandisk cards listed at Sandisk's own website, or at any of the retailers they link to...

NZtechfreak said:
From Ebay? You're sure its genuine? I don't see Class 4 Sandisk cards listed at Sandisk's own website, or at any of the retailers they link to...
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Fairly sure, but as always not 100%. The seller in question sells masses of SD cards and they're quite well known for being legit. Plus a few people on other forums have bought them and vouched for them.
Still, can't be certain though
Here's the link: http://cgi.ebay.com.au/SanDisk-32GB..._Electronics_Memory_Cards&hash=item2c59008a55
EDIT: Although the picture shows Class 2, but it mentions Class 4 in the description...

what about this one? £12.45 32gb sandisk
http://cgi.ebay.co.uk/100-32GB-Micr...1?pt=LH_DefaultDomain_205&hash=item3cb75af7b5

How about this?
http://www.amazon.co.uk/Lexar-32GB-...2ZTM/ref=sr_1_1?ie=UTF8&qid=1304244962&sr=8-1

What speed and/or Class card do you use for your memory card?

Hey
Im sorta "hell bent" on getting a 32GB microSD Class 10 card ( http://forum.xda-developers.com/showthread.php?t=1031312 ) but they are very limited to find. I want a Class 10 because of data transfer and the snapping of pictures/video taking is alot quicker.
I just want to know what class did you get, for what purpose, and what do you use your mobile device most (taking pictures, internet, calling, etc).
Just so everyone knows (just in case):
The Speed Class Rating is the official unit of speed measurement for SD Cards, defined by the SD Association. The Class number represents a multiple of 8 Mbits/s (1 MB/s), and meets the least sustained write speeds for a card in a fragmented state.
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Click to collapse

Hey,
I was really keen on getting a class 10 32Gb too, but they are very expensive. In then end I opted for a 16Gb class 10 as Play.com had them on offer a month or so ago. I got a sandisk one. Just had a look for a link, but I don't think they have them now.
Guess you could get it anywhere though. I paid £15 including delivery.
I've done a couple of measurements and it's definitely performing at class 10 speeds. I have an HD2 running an Android Gingerbread SD build and the speed has been more than adequate.
My use is mostly internet, texts and calls. I have done some video/photo stuff since getting the card and it's definitely fast enough.
I used to have a class 6 PNY 8Gb one in there and it's a hell of an improvement, especially now I'm on an SD build. The only thing I would say is android takes a fair while to do it's 'preparing SD card' business when I turn the phone on, but no other issues to report. the new card seems to have helped with the hang issues on installing market apps too, which is nice.
Also - did a defrag on it with Mydefrag (beautiful tool!), which seems to have helped too.
Hope that helps!

I still use my stock 8GB card I got with my phone. My main use is pictures and apps. Its a class 2.
Sent from my HTC Inspire 4G
XDA Developers Premium App

I'm currently using 2 32GB Sandisk cards... one is marked class 2, one is marked class 4, but both their average write speeds are pretty similar. They could accurately be marked as class 6.
But really, the class is not important to me. When it comes to choosing a card to use in my phone, I look for cards with quick access times and fast random read and write speeds. Class ratings are really only important when the cards are going to be used in a digital camera or be used as a flash storage drive where you will be transferring large files back and forth.
When it comes to cell phones, a card that can quickly access files and can read/write to many different parts of the card quickly is much more important than a card that can write sequentially fast. You may be able to take large pictures with the camera more quickly with a higher class card, but many cards sacrifice their random access speeds to get that high sequential write speed. This can cause lags and performance loss when running apps or system files off the higher class cards.
The best cards to generally use in cell phones is a class 2 or 4. Many class 6 may perform well, too. There may even be class 10 cards that don't sacrifice that random access speeds. Quality and brand are generally much more important than class to get good access speeds and random read/write speeds.
I really think there needs to be a new rating system for access speeds and random speeds. In general, the lower class cards have better random access speeds, but that's not always the case. There are plenty of class 2 and 4 cards that have terrible random access times, and many class 6 and even 10 that still have great random access. Unfortunately, there's no way to know how a card rates in these areas until you actually test it.
I've always had good results from Sandisk cards... and terrible results from Kingston.
Hopefully, since WP7 requires cards used with it to have good random access speeds, we might start seeing some lines of microSD cards that rate these speeds.
But for now, if you're using the card with wp7, or running android off the card, or running apps or other system files off the card, you will generally have better results with high-quality lower-class cards. I have only been using Class 2 and 4 Sandisk recently. Hopefully a new class and rating system is created for using these cards with smartphones. We are using them more and more for the purpose of internal phone memory... especially windows phone 7, and even with android you see more people making partitions on their cards to use as internal memory to run app and system files. We need a better rating system for cards, cause the current class rating is pretty much meaningless for smartphone purposes.

homescrub said:
I still use my stock 8GB card I got with my phone. My main use is pictures and apps. Its a class 2.
Sent from my HTC Inspire 4G
XDA Developers Premium App
Click to expand...
Click to collapse
Thanks but vote
Seiphr said:
Also - did a defrag on it with Mydefrag (beautiful tool!), which seems to have helped too.
Click to expand...
Click to collapse
Defraging a flash based storage device does nothing and actually makes its lifetime smaller.
zarathustrax said:
I'm currently using 2 32GB Sandisk cards... one is marked class 2, one is marked class 4, but both their average write speeds are pretty similar. They could accurately be marked as class 6.
But really, the class is not important to me. When it comes to choosing a card to use in my phone, I look for cards with quick access times and fast random read and write speeds. Class ratings are really only important when the cards are going to be used in a digital camera or be used as a flash storage drive where you will be transferring large files back and forth.
When it comes to cell phones, a card that can quickly access files and can read/write to many different parts of the card quickly is much more important than a card that can write sequentially fast. You may be able to take large pictures with the camera more quickly with a higher class card, but many cards sacrifice their random access speeds to get that high sequential write speed. This can cause lags and performance loss when running apps or system files off the higher class cards.
The best cards to generally use in cell phones is a class 2 or 4. Many class 6 may perform well, too. There may even be class 10 cards that don't sacrifice that random access speeds. Quality and brand are generally much more important than class to get good access speeds and random read/write speeds.
I really think there needs to be a new rating system for access speeds and random speeds. In general, the lower class cards have better random access speeds, but that's not always the case. There are plenty of class 2 and 4 cards that have terrible random access times, and many class 6 and even 10 that still have great random access. Unfortunately, there's no way to know how a card rates in these areas until you actually test it.
I've always had good results from Sandisk cards... and terrible results from Kingston.
Hopefully, since WP7 requires cards used with it to have good random access speeds, we might start seeing some lines of microSD cards that rate these speeds.
But for now, if you're using the card with wp7, or running android off the card, or running apps or other system files off the card, you will generally have better results with high-quality lower-class cards. I have only been using Class 2 and 4 Sandisk recently. Hopefully a new class and rating system is created for using these cards with smartphones. We are using them more and more for the purpose of internal phone memory... especially windows phone 7, and even with android you see more people making partitions on their cards to use as internal memory to run app and system files. We need a better rating system for cards, cause the current class rating is pretty much meaningless for smartphone purposes.
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Great post as in the other thread I may have to go with a Class 4 (as there are even less Class 6) card as it will also lower the price in my budget. Cant have everything...

I got a good deal on a Samsung 16 gb class 2, figured I'd go for it because I don't really use my phone for too much HD recording . However, it consistently benchmarks at class 6 speeds.
Yes, I did vote

32gb sandisk class 4

No clue, is there a program which can be used to check it in a SGS?

johan81 said:
No clue, is there a program which can be used to check it in a SGS?
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h2testw
Thanks

Thanks for all the votes
It seems since Im on a budget, Im going to have to go with a Class 4 even though it hurts as I (thought) a Class 10 was needed. I just hope I dont notice it when taking pictures.
SanDisk without a doubt right?

riahc3 said:
SanDisk without a doubt right?
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Im tempted to make a thread about this as well
I just like to make sure what I buy before I do it. Makes me more sure about what Im buying.
Thanks to everyone who has helped me in these 2 (well problably soon 3) threads. I appreciate it

riahc3 said:
Im tempted to make a thread about this as well
I just like to make sure what I buy before I do it. Makes me more sure about what Im buying.
Thanks to everyone who has helped me in these 2 (well problably soon 3) threads. I appreciate it
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Definitely Sandisk....if getting 32GB, look for model # ending in B35A or B35N. I think that's the one I got. I'll double check tonight and let you know. It was listed as class 2 when I ordered it, but it was marked class 4 when I got it, and it had sequential write speeds equal to class 6 (6MB/Sec). I also have a 32GB with model # ending in A11M... this one was mark class 2, but I think newer ones are also marked class 4. Not sure if the newer ones marked class 4 have better performance than the ones marked class 2, but mine which is marked class 2 could also easily be marked class 6 and be as fast in sequential write speeds as most class 6 of other brands... but the class 2 A11M is not quite as fast as the class 4 B36A that I have in both sequential write/read and random read/write & access times. But like I said, the newer A11Ms marked as class 4 may have better performance than the ones marked class 2, and the performance difference between my 2 32GB Sandisks is not very big.... both are VERY good cards in overall performance.
I got both my cards from provantage, I believe.

zarathustrax said:
The best cards to generally use in cell phones is a class 2 or 4. Many class 6 may perform well, too. There may even be class 10 cards that don't sacrifice that random access speeds. Quality and brand are generally much more important than class to get good access speeds and random read/write speeds.
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Hey zarathustrax, I'm maintaining a microSD benchmark results thread and we have quite a few results now, and it backs up everything you are saying. The 32GB Class2 Sandisk (when it was available) owns everything on random writes. Followed by the 32 Class4 Sandisk.
By comparison, a 32GB Class10 Lexar is benching 350 times slower for random writes than the Sandisk. And yet only offers a doubling of sequential write speed.
Additionally, I maintain an in-phone microSD benchmark thread too. But the results are pretty much cached out by whatever ROM you are running on your phone. So slow cards become much faster, and fast cards become much slower. In the end we found that all cards were performing at around the same speeds. Its only when you changed ROMs would you see a change in in-phone card speed.
Out of phone benchmark link...
http://forums.whirlpool.net.au/forum-replies.cfm?t=1582172
In-phone benchmark link...
http://forums.whirlpool.net.au/forum-replies.cfm?t=1468705

Thanks. Im going to read your links now and see if there are model numbers and get some cards (I should have already bought the card before yesterday)
Thanks again stumo5

Damn, no model numbers

Stores that are near me and deliver to me only offer Kingston lol...

Holy ****!
I have found one that has a Sandisk; The only problem is that on the webpage it says that it is a SDSDQM-032G-B35 but the picture shows a 2 written on the card, meaning Class 2. I pretty much refuse going from a Class 10 to a Class 2 and besides the price is 95....
Im going to call and get the model number anyhow....

Kingston 60 bucks
Sandisk 95 bucks
Man how they like to **** consumers in the ass Anyways, he said that what was shown to him was divided by categories and he couldnt tell me the exact model number as it just showed him prices and who supplied it but I rather pay on eBay a Lexar Class 10 at 96 rather than a Sandisk Class 2/4 at 95.
More comparisons: A Sandisk Class 2 32GB at 89 bucks on eBay.
I mean I really have to juggle and ask my self: Is it really worth it? Being on a slight budget, Im not sure.
stumo5 - Has anyone done tests in your microsd exam on TopRAM? I might get them at the end as the prices are just rapist ( ). zarathustrax, the price doesnt justify to me at the end, unless I will notice it.
My main dilema was how pictures were going to be taken as I imagine there will be a lag in picture when I press it and when it is actually taken. Also file transfers and installing/running applications from the SD card. Your explanation was great zarathustrax but Im not sure if its going to be worth the price.
My first smartphone (Nokia E70) I went with Kingston but it surprises me in a way that people talk so bad about Kingston in the flash memory card area.

And I now see on eBay a Sandisk 32GB Class 4 at about 75....More or less.

I'm currently using the 8gb one that came with my Desire Z although I have a class 6 8Gb somewhere that I bought but I haven't felt the need to swap yet for some reason I can't tell a difference

What Type Of MicroSDHC Class, Should I Buy For Arc?

Hey Ppl...
What Type Of MicroSDHC Class, Should I Buy For Arc?
Class 4, 6 or 10?
Right now i´ve Class 2

Its better to get the highest which is class 10 if u can afford..

The Classes guarantess a lowest speed while newely formated
class 2 is 2MB/s
class 6 is 6MB/s
class 10 is 10MB/s
and so on
but with luck a class 2 card can outpreform a class 6 card but you never know untill you have bought it.
the use of a higher class is more important how often you transfer big amout of files/data from and to your phone (this is when you will notice a slow card)
everyday use the class 2 card that is shipped with the phone works perfect

I'm going for a 16GB Kingston Class 10 for mine, might go 32GB but that'll depend on how much I get for my X10 on ebay.

XperienceD said:
I'm going for a 16GB Kingston Class 10 for mine, might go 32GB but that'll depend on how much I get for my X10 on ebay.
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Put my X10 on ebay yesterday!
How much you asking for it?
For no OT, I bought a 32 GB Lexar class 10 MicroSDHC

LususNaturae said:
Put my X10 on ebay yesterday!
How much you asking for it?
Click to expand...
Click to collapse
Not sure yet, it's a bit weared so not expecting a great deal.

Here's the thing: the class of an SD card only defines how fast you can *write* to it. The read speeds of all cards tend to be the same regardless of class.
What a faster class of SD card will get you:
* faster copying of files from PC to SD, e.g. music, video
What it won't get you:
* a faster running phone (i.e. no 'snappier' performance)
* apps loading faster
* faster copying of files from SD to PC
* music/video playback improvements
* faster installation of apps - these are stored in internal memory, and even for builtin apps2sd the limiting factor tends to be the download speed
What it might get you:
* faster stills camera operation (havent checked for the arc, there may be bottlenecks elsewhere in the system, e.g. cpu)
* i thought it might solve the video capture glitching, but apparently the new firmware has fixed this regardless of SD card class.
* some apps which write a lot of data to SD card may run faster (note however that for most apps data is stored in internal storage)
Nothing inherently wrong with getting a faster card, just dont delude youself you'll see much of a difference in day-to-day operation.
Oh, i forgot, EXCEPT one other thing: If youre using 'full' apps2sd on a rooted phone (i.e. with an ext2 partition moving all apps+data+dalvik cache onto it) it will definitely help to have a faster class of SD card. Dunno if anyone really still does that these days...

I've always found going bigger and faster to be best, but valid points made.

daveybaby said:
Here's the thing: the class of an SD card only defines how fast you can *write* to it.
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That's incorrect - the class rating is a guarantee of both read and write speeds.
daveybaby said:
The read speeds of all cards tend to be the same regardless of class.
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Click to collapse
You can't guarantee that any more than you can guarantee that a Class 2 card will write at speeds higher than 2MB/s.
The only way to be sure of getting a card that will read at a certain speed is to buy the appropriate class.

Step666 said:
That's incorrect - the class rating is a guarantee of both read and write speeds.
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That's a nice opinion, but unfortunately it's just wrong.
Have a look at this. Notice they dont mention read speeds anywhere, that's because theyre already so fast regardless of class that it's irrelevant.
When you buy a class 10 SD card, youre spending your money on faster writes.
The read speeds of all cards tend to be the same regardless of class.
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Click to collapse
The limiting factor in read speeds is the interface, not the memory technology. I believe SDXC may have faster interface specs than SDHC (which in turn has faster specs than plain SD), but this is nothing to do with class, and make no difference if youre plugging them all into an SDHC device anyway.

Try reading that page again, it doesn't say that the class certification is a measure of writing speed, it says it's the bus-interface speed - it merely mentions write speeds as examples of why you would need higher speeds in real life.
The read speeds that the cards are actually capable of may well be higher but in practice the write speeds are almost always higher too - but there's no guarantee they are.

Step666 said:
Try reading that page again, it doesn't say that the class certification is a measure of writing speed, it says it's the bus-interface speed - it merely mentions write speeds as examples of why you would need higher speeds in real life.
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So it's just a coincidence that nowhere does anyone mention read speeds, only write speeds and recording, when talking about flash memory. Because nobody's interested in read speeds, right?
Look, the read speeds of flash memory devices are stupidly high compared to write speeds (and always have been), and are limited by the interface, the write speeds are limited by the technology of the memory itself (which is the bit all of the manufacturers have spent millions (probably billions actually) improving over the last 10 years.
I hate quoting wikipedia articles but:
The Speed Class Rating is the official unit of speed measurement for SD Cards, defined by the SD Association. The Class number represents a multiple of 8 Mbits/s (1 MB/s), and meets the least sustained write speeds for a card in a fragmented state.[17]
These are the ratings of all currently available cards:[14][24]
Class 2, 2 MB/s
Class 4, 4 MB/s
Class 6, 6 MB/s
Class 10, 10 MB/s
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I can see this going round in circles. From what I've read, basically, if you put a class 10 card in a phone that has been running a class 2 card then you're not going to see the difference like you would putting 4GB of memory in a PC that has been running on 512MB, but having a higher class of card will improve some areas behind the scenes so to speak.
If I didn't have an X10 to sell then chances are I'd stick with my class 6 Samsung but as I'll have the money to go class 10 I am doing.

daveybaby said:
Look, the read speeds of flash memory devices are stupidly high compared to write speeds...
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And?
Real-world write speeds on cards are generally higher than their class rating would suggest but you are only guaranteed the speed corresponding to the class the card is.
Exactly the same applies to read speeds, they will most likely be much higher in real life but you are only guaranteed the speed that corresponds to the rated class of the card.
The class of a card guarantees minimum read and write speeds but both will likely be noticeably higher in real life.

Class has nothing to do with read speed period. Manufacturers only guarantees the write speed based on classifications because read speed will only be the same for all class of cards. Try the "Sd Tools" app if you don't believe me.
Therefore, unless you are using the defunct "app2sd+ data, dalvik", there should not be any discerning difference except for its higher price.
Sent from my LT15i using XDA App

Step666 said:
And?
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And the read speed limit is defined by the interface implementation not by the class of the card. When i say flash read speeds (i.e. reading data from the cell) are fast, i mean theyre to all intents and purposes instantaneous, they always have been - they havent gotten any faster in the last 20 years - it's inherent in the technology. The thing that takes all the time is shuffling the bits of data across the serial interface.
It's entirely possible for a class 2 card by one maufacturer to have faster read speeds than a class 10 card by another manufacturer. It's entirely possible for the same card to have different read speeds in different devices due to the interaction of the interface implementations (subtle timing differences). Write speeds arent affected by this as much because the bottleneck is the large amount of time it takes to erase a cell and rewrite it.
Note that if you have a really old class 2 card, it's probably going to have much slower read speeds than a brand new class 10 card. This is not inherently due to the class of the card, it has everything to do with the fact that manufacturers only implemented faster interfaces to handle class 10 cards once the technology to *write* at this speed became available. Due to economies of scale they implement these faster interfaces across the board. New class 2 cards will be able to read as fast as new class 10 cards.
That's all i'm going to say on this matter, if you dont believe me you dont believe me, i'll agree to disagree.

daveybaby said:
That's all i'm going to say on this matter, if you dont believe me you dont believe me, i'll agree to disagree.
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I'm afraid I don't, we'll have to disagree.

The sdhc that came in the box has a class 2 rating in it but using sd tools, it writes at 6mb/sec average, bursting at 9mb/sec. Read speed is the same as my older 8Gb class 6 at 19-20mb/sec.

Step666 said:
I'm afraid I don't, we'll have to disagree.
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Cool

I have Sandisk Micro HDSD 16GB Class 2 but in SD Tools Write Speed: 10.1Mb/s, Read Speed: 27.5Mb/s

[Q] The Best 32gb Card? Brand? Class?

I wanna get a 32gb best class card but I have no idea which one to get.. Any pointers?

NeeceeBabe said:
I wanna get a 32gb best class card but I have no idea which one to get.. Any pointers?
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Basically, stay away from the cheap eBay auctions for them. You'll often get a fake-brand claiming to be SanDisk, but it's really not.
Stick with legit SanDisk or Transcend.

Amazon and Newegg have had some good deals.

AData has a true class 10 speed with 32GB. I use it on my Cowon J3 music player. It's very fast, faster than the Lexar Class 10 that I have.
http://www.adata-group.com/index.php?action=product_feature&cid=7&piid=37

nraudigy2 said:
AData has a true class 10 speed with 32GB. I use it on my Cowon J3 music player. It's very fast, faster than the Lexar Class 10 that I have.
http://www.adata-group.com/index.php?action=product_feature&cid=7&piid=37
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I hope I can find one. seems like 32gb class 10 are REALLY hard to find.

NeeceeBabe said:
I hope I can find one. seems like 32gb class 10 are REALLY hard to find.
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Here's some...
http://www.newegg.com/Product/Produ...n=micro sd 32gb&name=Class 10&Order=BESTMATCH

I'm curious: where would we see the advantage of a Class 10 card on our phones? Outside of copying files to/from them faster, I'm not sure there's anything we're doing on them that would benefit from it. Anything concrete anyone can suggest that I'm not thinking of? The photos aren't anywhere high-res enough to require it, and the camera's not capable of taking them in a fast enough burst mode to need it, and I'm assuming even the 1080p video capture doesn't need it or Samsung would have had an * in their advertising to let us know. So that leaves me to assume I could probably save some money on a lower class and be just as happy...

TurboFool said:
I'm curious: where would we see the advantage of a Class 10 card on our phones? Outside of copying files to/from them faster, I'm not sure there's anything we're doing on them that would benefit from it. Anything concrete anyone can suggest that I'm not thinking of? The photos aren't anywhere high-res enough to require it, and the camera's not capable of taking them in a fast enough burst mode to need it, and I'm assuming even the 1080p video capture doesn't need it or Samsung would have had an * in their advertising to let us know. So that leaves me to assume I could probably save some money on a lower class and be just as happy...
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So your saying a class 6 or 4 should be fine?

Would it affect flashing roms or running apps2sd?
TurboFool said:
I'm curious: where would we see the advantage of a Class 10 card on our phones? Outside of copying files to/from them faster, I'm not sure there's anything we're doing on them that would benefit from it. Anything concrete anyone can suggest that I'm not thinking of? The photos aren't anywhere high-res enough to require it, and the camera's not capable of taking them in a fast enough burst mode to need it, and I'm assuming even the 1080p video capture doesn't need it or Samsung would have had an * in their advertising to let us know. So that leaves me to assume I could probably save some money on a lower class and be just as happy...
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Sent from my SPH-D710 using XDA App

Transcend cards are great. I use them in my dslr when i film. I can not be let down when im in the middle of a production.
Class 6-class 10 will be good enough for the phone. A class 6 16gb I've read has the best overall speeds
Sent from my SPH-D710 using Tapatalk

Class 6 will do just fine. The extra expense of the Class 10 is not worth it right now. As a previous poster hinted to, the phone does not do anything fast enough to take advantage of the full Class 10 speeds.
It might help for initial file transfers if you transfer Movies to it or something like that, but how often do you really do that?

lazloe said:
Class 6 will do just fine. The extra expense of the Class 10 is not worth it right now. As a previous poster hinted to, the phone does not do anything fast enough to take advantage of the full Class 10 speeds.
It might help for initial file transfers if you transfer Movies to it or something like that, but how often do you really do that?
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Okay Thanks... should be easier to find that lol. But I don't, I just like the best of the best p

I have also looked around the net quite a bit regarding this issue (is how I came to my conclusion above). One more thing I would like to add is to make sure you buy Retail or from a known good supplier to be safe ... like Newegg... not Ebay or Amazon.
Most quality brand name cards will perform their benchmark tests at or above their ratings. This is why Class 6 is good enough for our uses right now until something better than 10 drops and pushes the 10's down in price. (Look to the future whenever you can get a deal)
Here is Sandisk's information on classes:
http://kb.sandisk.com/app/answers/d...speed-ratings-(performance)-for-sd/sdhc-cards
I doubt the cameras on our phones are recording at more than 6MB/s.
I would love to see some stats on this though.. you know, in case I'm wrong.
(which I don't think I am)

NeeceeBabe said:
Okay Thanks... should be easier to find that lol. But I don't, I just like the best of the best p
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I like your style Neecee. Hope you get your phone soon
Sent from my SPH-D710 using xda premium

JohnCorleone said:
I like your style Neecee. Hope you get your phone soon
Sent from my SPH-D710 using xda premium
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Sighs, Just might have to drink some wine to help with the pain. Letstalk SUCKS!

It speeds up everything. Application manager loads faster, faster scan at startup, apps in microsd will load faster, transfering/copying files from or to pc/internal memory, ect...