Pros:Fastest standard SD Card I've tested!
Cons:Half as fast as manufacturer's claim. Pricey compared to "standard speed" cards.
The Bottom Line: If you need a company to guarantee fast writes on the package, then the SanDisk Extreme III SD Card is for you.
With flash memory makers always putting claims about their product's performance on the packaging, how much of that is true? There are several flash memory I've tested that doesn't seem to be anywhere close to the claims, and a few that meet or exceed expectations.
Recommend this product?
SanDisk claims that their SanDisk Extreme III 2GB SD Card can read and write at 20 MB/sec. That's sounds unbelievable, since the fastest card I've tested was 11 MB/sec, and write speeds for flash cards seem to be their Achilles heel. I've seen read speeds of 36 MB/sec before, and that's saturating the USB 2.0 bus!
So how did the SanDisk Extreme III 2GB SD Card do?
In the Box
SanDisk recognizes that being a premium product, the Extreme III shouldn't just come in a cheesy packaging. So, it's well packaged in a cardboard box with fancy retail designs. It comes with the SD card itself with a plastic holder. It also comes with a Velcro-flap carry case adorn with SanDisk's own logo.
Since I found out that the built-in card reader on my laptop is holding me back (read my review where that skewed my results), I since purchased a Dynex card reader that claims to be able to read SDHC cards. It should also be able to read and write to flash cards much faster and without restrictions as well. The write speeds for the A-Data microSDHC card seem to have benefited from the changing the card reader. So I decided to use the same reader to test the SanDisk Extreme III.
I copied a 504 MB solid file to the empty card and then read it back. Writing to the Extreme III took 55 seconds, which translate to a 9.16 MB/sec transfer rate. This is a far cry from the claimed 20 MB/sec write speeds! It's still pretty quick for a SD Card, however.
When reading the file back, I managed a 14 second read speed, which translate to 36 MB/sec even! This is about where the USB 2.0 bus is saturated. It is also way faster than the claimed 20 MB/sec rated read speed.
Is SanDisk's marketing people using an average for the combined read/write speed rating? That's a very deceptive way of doing business. But alas, that may be it.
The cost for the SanDisk Extreme III 2GB SD Card is $38.25 at Newegg, which isn't too bad for a high-speed card. However, I purchased the A-Data 4GB microSDHC Class 6 card, which comes with a microSD to SD adapter, is faster with write speeds (11 MB/sec). And the cost for the faster A-Data card is $32 at Fry's Electronics. I also had a $5 mail in rebate, which brought the cost down to $27! It's cheaper, have twice the capacity, faster writes, and works in both microSD and SD slots! The only downside with the A-Data card is that it is a SDHC card, which means you'll need to buy a different card reader, adding more to the cost.
If you have a device that is not SDHC compatible and need fast writes, you'll have no choice but to go with a fast standard SD Card. The SanDisk Extreme III 2GB card is such a card you'll need. It is quick, but only performs half as fast as what SanDisk promise. Still, 9 MB/sec is still faster than most flash media usually writes at.
Or you can always purchase those cheap SD Cards on sale at Microcenter (I picked up a few 2GB card for only $17), and chance that they write at a speed is acceptable to you. When I tested one, I was pleasantly surprised to see it write at 6 MB/sec! That's not bad for a cheap card, and is fast enough for my 10 Megapixel digital camera, which at the highest quality setting create files anywhere between 3 to 4 MB per picture.
If you rather buy something that guarantee a fast write speed, then paying a little extra for the SanDisk Extreme III may be a good idea.