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SIM - Subscriber Identity Module for mobil phones
Smart card or or integrated circuit card (ICC) (ISO 7810 and 7816 Card Standard)
Credit Card with imbedded ICC.
PC Card - PCMCIA - 85.6 mm long and 54.0 mm wide
There is a brand name Ultra who's basic card is a 40X write speed. Price a/o Mar. 2006
Micro SD - Class rating|
Any Micro SD card 4GB and above are SDHC (High Capacity).
Class is an minimum non-fragmented sequential write speed. Used for device compatibility. The X rating to the left is the maximum speed.
See: A 2009 discussion about microSD card speeds- xda-developers forum
Android will read up to 32 GB
Read Speed of a Standard CD-ROM = 1.2MB/s One forum comment said, "As an example I've written HD video from the camera to a 16GB Sandisk Ultra Mobile, 16GB Class 6 Transcend & 32GB Sandisk Class 2 and there's no speed difference in writing/playing back the video file.
The only place you will see any speed differences is when transfering data from a PC to the card."
These speed notations may not be consistent among manufactures.
Write speeds are slower than read speeds.
Most camera manuals don't tell you what speed of flash card you should buy, usually recommending a type and maybe a manufacturer (who has often paid to be included in their recommended list). If your camera has resolution under five mega pixels, the speed rating of the flash card won't matter much. In fact many cameras will not work well with ultra high speed cards of 66X and 150X speeds because of the special formatting used to achieve these high speeds. The improvement you are likely to see in a higher rated card will be minimal and undetectable.
Professional photographers using professional-grade cameras should use high-speed flash (40X [Class 6] - 66X [class 10]). If your camera has a pixel rate more than five mega pixels, you will benefit from a flash card with a higher speed rating. If your camera has a resolution less than five mega pixels, simply use cards rated less than 40X, this way you can ensure compatibility and not spend money unnecessarily on higher rated cards.
Secure Digital (SD):
SanDisk Ultra II Plus SD Card can be folded to fit directly in a USB port. 1G = $90
CompactFlash (CF) cards provide complete PCMCIA-ATA functionality and compatibility and can be used in a PCMCIA slot with an adapter.
which brand of class 6, 16GB microSD should i get? - Android Forums, says,
32GB USB flash memory sticks (thumb drives), now available at $120, are an alternative for backup.
Listed Data Transfer Rate are 19MBps Read 13MBps Write
Actual for a 32GB flash stick are:
Sequential Read Write 32 GB Corsair Flash Voyager 22 MB/sec 10 MB/sec 32 GB OCZ Rally 2 30 MB/sec 22 MB/sec 32 GB Patriot Xporter XT 31 MB/sec 17 MB/secActual report on Amazon for OCZ OCZUSBATV32G 32GB ATV USB:
2.5MBps write (3-5 hrs for 25GB) for a lot of small files. Large files copy faster.
When I formated it as a DOS (Fat32) disk it wrote at about 1.5 MB/sec
When I formated it as Mac OS Extended (Journaled) and was about 2 MB/sec.
A 2GHz dual processer Mac Pro gave 4 MB/sec
When I partitioned a 32GB OCZ ATV into 2 FAT32 partitions and copied from a Mac PowerBook G4 wuih USB 2.0 it 2 hrs to copy 350 MB. 0.05 Mb/sec.
On a PC witn Win 2K: Read Write OCZ 32G 0.97 MB/s 0.59 MB/s Cruzer 4G 0.97 MB/s 0.94M B/s Windows will not read more than one partition on a removable drive.
You can get software to flip the removable drive bit so it will work.
USB 2 was reported to be slower on Macs (may be improved in panther OS X 10.3)
See: X-Bit Labs rreview of 32 GB USB flash drives:
Formatting - File Systems:
Note that you can use any disk utility to format SD cards, such as Gparted or the disk utilities built-in to Windows or OS X. But the SD Association recommends using their own SD Formatter to avoid formatting the “Protected Area” that exists on some SD cards that incorporate security features.
Flash USB (thumb) drives
Speed Tests at MobileTechReview.com
Reviews and FAQ: Memory Cards at MobileTechreview.com
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