150x SD card vs class 6 SDHC SD card - speed comparison.

On my PocketPC PDA I was using Transcend 150x 4gb SD card. Recently I
replaced it by Transcend class 6 SDHC 8 gb card. My impression is that
my old 150x card is faster that the new class 6 SDHC card. Is there
any way to verify if my impression is true?

Thanks,

Zalek

 

I suspect your observations are correct.
150X is pretty darn fast.
To verify this, just clean up the 4GB card and download a BIG folder of
pictures (3-4 GB)and time how long it takes to download the files.
Repeat, downloading the same folder to the clean 8 GB card.
Bob Williams

 

| zalek wrote:
| > On my PocketPC PDA I was using Transcend 150x 4gb SD card. Recently I
| > replaced it by Transcend class 6 SDHC 8 gb card. My impression is that
| > my old 150x card is faster that the new class 6 SDHC card. Is there
| > any way to verify if my impression is true?
| >
| > Thanks,
| >
| > Zalek
|
| I suspect your observations are correct.
| 150X is pretty darn fast.
| To verify this, just clean up the 4GB card and download a BIG folder of
| pictures (3-4 GB)and time how long it takes to download the files.
| Repeat, downloading the same folder to the clean 8 GB card.
| Bob Williams


http://www.flashmemorytoolkit.com/download.html


the free prog asks for registration code each time it starts but you just
hit 'try' and you're into the full kit

small free and it'll write junk files to your card and read them back to
give you good speed comparisons - don't forget to delete these files
afterwards

I had some *very* surprising results, which supports the many sites out
there that state what manufacturers claim is often not quite true

hop this helps

Karl

 

| On Tue, 27 May 2008 17:31:38 +0800, "k" <>
| wrote:
| Flash Memory Toolkit is a handy program but it can't provide
| information used to decide the manufactuer claim is untrue.

no it can't. the tests were run by companies and reviewers who ran both
comparitive tests and who had access to far better test equipment than I

however, using the same PCMCIA 5 in 1 card reader on an SCSI PC card slot, I
have found some low end microSD card providing surprising comparivite speeds
when also testing higher end SD cards

Likewise with CF cards on an IDE cable


| The manufacturer claim is based on an ideal environment and
| transfer, while many of the following can cause a lower
| rate:
|
| - Benchmark write access pattern

formatted cards tend to get around thee worst limitations

| - Inefficiencies or bottlenecks in the device using the
| card.

IDE is pretty good.. SCSI not bad either


| - Inefficiencies or bottlenecks in the (PC USB) card reader.
| - Inefficiencies or bottlenecks in the PC USB itself.

I've skipped the USB parts.. though comparable results wer found using the
inetrnal USB bus and an internal reader
|
| - Inefficiency in the filesystem
|
| - File sizes used for the test, or used in device operation

of course - again though, comparitive speed tests are better than a poke in
the eye



| Consider that many flash memory cards/USB drives/etc using
| current technology are rated around 30MB/s read speed, and
| yet many PCs can't get 30MB/s in some uses or tests, over
| USB, even if a much faster device like a good modern hard
| drive was connected via external enclosure instead of a
| flash drive. Clearly this means the bottleneck on a good
| spec'd flash drive is often elsewhere.


comparisons are pretty much the only useful tests a consumer can do

k

 

According to Galbraith, the apparent speed of a memory card depends a
lot on the camera it is used in. Could be very fast on one device but
slower on another, and one card could be faster or slower than another
depending on the camera.

http://www.robgalbraith.com/bins/multi_page.asp?cid=6007

Archibald

 

| According to Galbraith, the apparent speed of a memory card depends a
| lot on the camera it is used in. Could be very fast on one device but
| slower on another, and one card could be faster or slower than another
| depending on the camera.

and in a pocket PC i'm sure its the same, however as I'm sure no camera
owner cares which camera is fastest, rather they'd be more concerned which
media is fastest for them, and a comparative speed would be more use than
any raw figures

say like for this, where the hardware is fixed and the media varies..
http://wiki.eeeuser.com/diskbenchmarks

"Please note that numbers from different benchmarks are actually not
comparable to each other! "

 

| On Wed, 28 May 2008 08:56:05 +0800, "k" <>
| wrote:
|
| >
| >| >
| >| According to Galbraith, the apparent speed of a memory card depends a
| >| lot on the camera it is used in. Could be very fast on one device but
| >| slower on another, and one card could be faster or slower than another
| >| depending on the camera.


| >and in a pocket PC i'm sure its the same, however as I'm sure no camera
| >owner cares which camera is fastest,


| You might feel you are sure but it is not so. Many (most?)
| cameras are slower than what are now dirt cheap flash cards
| if you don't need over 4-8GB (or higher in the future), so
| the speed of the camera is what determines how long one has
| to wait inbetween shots. Sometimes the camera has a
| reasonably sided buffer, <clipped>


I beg to differ but it *is* so.

The point being that the camera is the non-variable in the equation, the
memory card is the variable. The computer is the non variable, the pocketPC
the non variable .. the card again is the variable that we're discussing.
No one asked which bus is faster, which CPU gives the faster transfer - the
original poster wanted to know (as per the subject line) how to do a speed
comparison on an SD card - that's the variable. I have a pile of CF cards I
do noty use in my cameras because the transfer speed is sooooo slooow (!)
I know my camera will never be able to dump data at SCSI speeds but in the
case of these cards, they are the bottleneck. I even speed tested them with
the program I mentioned to get a *comparison* with my other cards and yes,
they are appallingly slow.

And in using the program I suggested I was very surprised to find a cheapy
Chinese microSD card was a *lot* faster than my horribly expensive high
speed CF cards. I was delighted to discover this, because although I wont
use the microSD in a CF adapter in my camea for the resons you point out, I
*will* use it in my pocketPC where the speed actually is noticable

The original posted wanted to know "My impression is that my old 150x card
is faster that the new class 6 SDHC card. Is there any way to verify if my
impression is true?"

the program I suggested would allow him to determine this (that card A is
faster / slower than card B)


me:
| >... rather they'd be more concerned which
| >media is fastest for them, and a comparative speed would be more use than
| >any raw figures


| Yes, that too is important. Remember that many people
| aren't reading from the camera, they'll take the card out
| and pop in a second empty one leaving the reading to another
| device... probably a USB card reader.

yes fortunately! Though I'm still astonished to discover how many people
use the rotten bundled software and link via the camera. I work with
photographers a lot, and I still find even pros that do this!


to each other! "
|
| That is useful, yet one person's goal is not always
| another's. If performance matters it's not just a matter of
| picking the memory but also the device reading and writing,
| especially when it is the more costly and time consuming
| item to replace if a bad choice was made.

of course you're right. but again if the original posted wanted a speed
comparison in his particular working environment, there's not better way
than to test it in his environment. benchtests are nice, but we are all
really concerned with how it affects us in our own personal real world

karl