Database Users

Class 6 for apps to sd card?

i have a class 2 sd card that is 4gb. i read that you need class 6 for apps to sd card? will it not work on class 2?

It'll work but it'll just lag your phone down whenever any writing is taking place since the write speed is only 2mb/s compared to a class 6, 6mb/s.

Keep in mind that SDHC "class" system is only a guaranteed minimum. There are some class 4 cards out there that actually out perform some class 6 cards. Do your homework (read:google) and get a card that is > 8MB/s write and > 9MB/s read and you will max out the speed capabilities of your G1.
I can personally verify that the AData class 6 8G and the SanDisk class 6 8G both outperform the G1's capabilities. Also, from what I have read, the SanDisk class 4 16GB also outperforms the G1's capabilities.

Also, I have found that even though the SanDisk and the AData cards mentioned above exceed the G1's capabilities, the AData card is a better card for the G1 (in my particular case.) For some reason my Sandisk card can only get 6.5MB/s write and my AData card can get 8MB/s+ write speed on the G1.
Link to speed tests (please add to it if you have more info)
http://forums.t-mobile.com/tmbl/board/message?board.id=AndroidHardware&thread.id=357

i have a class 4 8GB card and i moved my apps to the sd card about a month ago...it was VERY laggy, so i went back to keeping the apps in the G1's internal memory.
i will try again when i get a class 6.

I have a class 2 16GB Sandisk card, and I have to say - there are no lags whatsoever. The card is much faster than the stock 1GB one, and if moving applications, you don't need that much write speed - the read speed is much more important. I can get 14 MB/sec read speed via cardreader with this card, while the stock 1GB one gives 5 MB/sec only (tested with hdparm).
Just remember - move only applications, NOT their data or caches (which is really unstable anyway). You should have no problems with speed this way - application startup is still fast (if a program is 7 MB, it needs 0.5 sec to be read, which is perfectly acceptable), and you still write to the phone's internal memory.

Transcend 16GB Class *6* Micro SDHC Speed Test

Hi All,
Just got myself a 16GB version of one of these:
http://www.transcend-uk.com/Products/ModDetail.asp?ModNo=195&SpNo=1&LangNo=0
to replace the stock 8GB Class 2 card that came with the phone. Unpackaged carefully to avoid dribbling on it
Have run benchmarks using both SKTools and Pocket Mechanic and ..... approx 5% SLOWER than standard card!! Have got SDTuneUp loaded, am I missing something glaringly obvious here???
SKTools summary results:
8GB Class 2 Sandisk (supplied with phone):
Buffered Write speed 910 KB/s
Read speed 7119 KB/s
16GB Class 6 Transcend:
Write speed 859 KB/s
Read speed 7021 KB/s
Could the glaringly obvious thing be *don't buy Transcend cards* ??!!! Am I benchmarking with the wrong software (figures vary greatly between the 2 apps but summary is the same - this card is slower)
Any tweaks I'm missing?
Cheers.
Bones.

Is this with the card in the phone or in a card reader?

Most likely it's the limitation of the phone. Try some desktop benchmarks with a good card reader.
You won't gain much speed from higher speeds cards on a phone.

ez2remember said:
Most likely it's the limitation of the phone. Try some desktop benchmarks with a good card reader.
You won't gain much speed from higher speeds cards on a phone.
Click to expand...
Click to collapse
hmm so whats the point of buying a higher class SD card?

Benchmarked in phone. I'll try in my card reader tomorrow. Got to say I'd be very disappointed if it's a hardware limit in the phone, class 2 cards are much cheaper than class 6 and HTC should have made this apparent if this is the case...
Will update when re-benchmarked, anyone got an comparison stats?

one comparison Class 6 to Class 4
At hand a Transcend 16gb Class 6 and Toshiba 2gb Class 4 SD cards measured in Thinkpad card reader:
Crystal Disk Mark mb/s
Transcend/Toshiba
Seq: 14.78/12.11 read 8.755/5.315 write
512K: 14.76/12.09 read 1.982/2.010 write
4k: 3.114/3.216 read 0.025/0.025 write
Not much there to recommend Class 6

Are you sure you have 8GB class 2 sandisk card? I got class 6 with the ppc.
My results in SKTools:
write: 642 KB/sec
read: 2963 KB/sec
That's 16GB class 2 sandisk card formatted with 32KB clusters. So i think your card is ok

Double post

Class6 does not mean that its faster its just "assure" you it can transfer up to 6mb/s. Thats prolly a device limit and not the card you should try it on a notebook or card reader outside phone. I thought the same when i bought a 16gb sdhc class6 SD for my axim - had no changes in speed at all =\

Memory Cards (SDHC)

Hi Guys,
I have a strange situation going on here with my micro SDHC cards. I have an 8gb Sandisk card class 2 and I just bought a 16gb Duracell class 4 card as I wanted a bit more space than 8gb for my desire HD (to be arriving soon).
Anyway the 16gb card arrived today in the post so I was bored and decided to do some speed tests on the 2 cards just to check. The class 4 card wrote at 4.1 mb/s which I presume is what it should do...right? How ever the class 2 card wrote at 13.5 mb/s!! I tested it several times with large amounts of data (using the H2testw program) and it kept getting the same results.
So it lead me to think that there is something wrong with my class 4 card (or its a fake). It does write at 4 mb/s but that is the bare minimum and surely it should be doing better? I got it off ebay and am now aware of the extreme amount of fake cards on there.
Anyone with a little experience on the matter care to offer me some insight?
Btw I will be using my phone for pictures and 720p recording so I want a fast card...but after this I am just confused.
Thanks

ccart said:
Hi Guys,
I have a strange situation going on here with my micro SDHC cards. I have an 8gb Sandisk card class 2 and I just bought a 16gb Duracell class 4 card as I wanted a bit more space than 8gb for my desire HD (to be arriving soon).
Anyway the 16gb card arrived today in the post so I was bored and decided to do some speed tests on the 2 cards just to check. The class 4 card wrote at 4.1 mb/s which I presume is what it should do...right? How ever the class 2 card wrote at 13.5 mb/s!! I tested it several times with large amounts of data (using the H2testw program) and it kept getting the same results.
So it lead me to think that there is something wrong with my class 4 card (or its a fake). It does write at 4 mb/s but that is the bare minimum and surely it should be doing better? I got it off ebay and am now aware of the extreme amount of fake cards on there.
Anyone with a little experience on the matter care to offer me some insight?
Btw I will be using my phone for pictures and 720p recording so I want a fast card...but after this I am just confused.
Thanks
Click to expand...
Click to collapse
Your card is just fine. The class of a memory card just tells you how slow it isn't, not how fast it can get.
Class 2 - Minimum of 2 MB/s performance.
Class 4 - Minimum of 4 MB/s performance.
Being a class 4, a minimum 4 MB/s is fine and passes the class 4 classification. But a 13.5 MB/s for a class 2 is great!

in my experience larger cards tend to be slower in real life situations anyway, i have found issues using slower cards so tend to stick with a minimum of class 6 (but then your class 2 exceeds that spec )

[Q] Testing the i5800 card speed

Could someone please try "SD Tools" and report you SD cards speeds. Im getting about 2.5 mb/s on both read and write. Tried several cards type 4 and 6. Cards reach full speeds when tested on a PC. Is that a limit for this phone or something is wrong with my unit? I had a Adata SD card die on me recently, too.. Could have been one of the fakes.
So, download and run "SD Tools" program on your i5800 and let me know the results. Also the type of sd card. I cant find any results on internet or this forum. I cant belive that i5800 is capped at 2.5 mb/s.
Thanks in advance everyone!

with the 1GB stock card, I got following result:
2.2 MB write speed
and
4.9 MB read speed.

8GB a-data
3,2 W
6,2 R

Hmm interesting. It seems something is wrong with my phone. I get 2.5 read on genuine 8GB class 4 sandisk card FAT32, at this moment. Thanks! Feel free to add the scores.

is it MB or mB, big difference!

stubborn_d0nkey said:
is it MB or mB, big difference!
Click to expand...
Click to collapse
MB/s
Hope "SD tools" can be trusted for Galaxy 3? Guess its time to RMA the phone.

-3.4 MB/s for writing
-4.7 for reading

Ok here is the concluson. I just got a new Class 6 Transcend card to make sure. Phone is OK. I got around 5.5 on both read and write. This is my third card so far.
No1: A-data 8gb Class 6 - died after 3 months of use, was always slow around 2.5 MB/s. I suspect it to be fake!
No2: Sandisk 8gb Class 4 - slow scores like its a Class 2 card. Also 2.5 MB/s. Tested it and its not one of the fake cards. Bought at a big reliable store. It seems Sandisk has some Class 2 cards marked as Class 4. WTF! Hope to return it.
No3: Transcend 8gb Class 6 - finally working as it should! Transfer speeds up to specs. Actually getting close to Class 10 scores with adapter under windows?!
I was either very unlucky or the SD card market is really crazy right now. Im just glad I dont have to return my phone. Thanks everyone for results!

Transcend 8gb Class 6- read=5mb/s
- write-4mb/s

Write = 3.7 MB/s
Read = 17.5 MB/s
Sent from my Lestatious v1.4.5.1 Galaxy 3 FROYO

Ya Mines also good But I dont understand wat CLASS

samsung 1 GB (i dont know class):
read: 2.5 MB/s
write: 2.4 MB/s
a-data 16 GB (class 10):
read: 4.9 MB/s
write: 4.4 MB/s

My cheap 2 GB Kingston:
Write: 3.7 MB/s
Read: 4.9 MB/s

[Q] Samsung micro SDHC 32GB "Pro" version - odd read/write scores

Was going for a Class 6 Samsung micro SDHC, but a Microcenter store I went to was out, and they offered the "Pro" version (which is a UHS-1 for transfer speeds of up to 70mb/s for writing and 20mb/s for reading). I said right away that my phone might not be compatible, but I'd try it.
So here are my puzzling results after the installation:
AnTuTu Benchmark: Read: 12.0MB/s, Write: 3.3MB/s
SD Card Tester: Read: 11.2MB/s Write: 3.24MB/s
A1 SD Benchmark: Read: 224.04MB/s, Write: 4.31MB/s (not sure what's up with that read value...)
These are with MIUI GB ROM with Android 2.3.7
Are these low speeds the effect of the UHS-1 not being quite compatible, or is my system really just that slow that it bottlenecks the card so dramatically?
I'll be looking to get a Class 6 card, which I know is plenty sufficient.. Hopefully it will not have such low transfer speeds with my HTC HD2.
For comparison purposes, my old Kingston 4GB Class 4 card scores 3.2MB/s write and 9.1MB/s read.
P.S.: Pretty sure this is a legit Samsung card, given the vendor and the appearance of the card, including all the fine print and serial number on the back.