Factory formatetd micro SD appears smaller then expected

[Joshike]

Does factory formatted SD needs sometimes a special formatting for Garmin?
and
what software is best to use for SD formatting?
Or
Please could anyone explain the Kingston factory formatted micro SD smaller size compared to other 2Gb SD media. As a result Europe NT 2011 (Map size 1,999,142,912 bytes) fits to mini SD below but not to micro SD, which appears to have more bytes on it.

micro SD Kingston
XP disk properties: 1,999,768,128 (1.83GB) Looks like might be formatted with some other sector size or are there hiddeb bad sectors?

When comparing size of other Kingston XP displays 1,999,800,896 bytes (1.83GB), there is a slight difference, does this difference and smaller formatted size really means bad sectors???

Kingston mini SD
XP disk properties: 1,999,175,680 (1.86GB) Map fits to card


SD Apacer 2GB
XP disk properties: 2,040,135,680 (1.89 GB) Didn't try to copy the map, but I believe there shpuldn't be any problem)

[bergfalke]

Try using the sd formatter by panasonic.
Download site:

http://panasonic.jp/support/global/c...oad/index.html

Do NOT use the windows disk formatter on sd cards.

[Joshike]

Thanks - but SD formatter didn't change memory size.

I don't understand - am I alone got micros SD cards which each are of a different size???
If not, then why no one doesn't complain about Europe NT 2011 unlocked map which doesn't fit to micro SD card?
Why a file of smaller size can't be written to micro SD card having slightly more room?
Perhaps it's this just a problem with Kingston? [No, I didn't bought these from Ebay but through retailer from Kingston direct :-)]
What brand micro SD cards do you suggest?

I have googled a lot but still a lot of questions and no replies. :-(

[Subnetmask]

I imagine it has something to do with the chips used to make the cards. I suspect not all chips are the same. I've always had good luck with SanDisk.

[timp4411]

It may that you got ripped off and bought a Counterfeit memory card.

I don't know where you got it from, but ebay is Loaded with Counterfeit cards.

The counterfeiter have gotten sophisticated and can make a card appear to be larger than it really is when you check it's "properties".

But when you go to format it, you can't get the amount of space from it that you should.

[Joshike]

I'm familiar with Ebay fake USB sticks.
But as I already mentioned - my Kingston micro SD's aren't counterfeit.
In fact Kingston site states:
"* Please note: Some of the listed capacity is used for formatting and other functions and thus is not available for data storage."

That's most likely the different size amount is due to hidden bad sectors.
Or it may be, that Windows XP just isn't able to access these properly - or isn't that weird, that less bytes don't fit to bigger SD?

To me it was just a surprise, that 2GB memory may be of the whatever size close to marked nominal...

[reegster]

I have found thi too quite annoying you would think they should advertise it as what it is..

[nosha]

Yes my 2gb is only 1.95gb which is why some guys like Kor@l make/supply a map set cut down to 1.7gb so they know it will fit on any make of 2.gb card, it doesn't just happen on micro cards - ALL cards once formatted to FAT32 etc will have a smaller capacity!

[t0rst3n]

Thanks - but SD formatter didn't change memory size.

I don't understand - am I alone got micros SD cards which each are of a different size???
If not, then why no one doesn't complain about Europe NT 2011 unlocked map which doesn't fit to micro SD card?

Two possible answers:

1) A "gigabyte" means different things depending on who you talk to. The convention in most cases is to mean 2^30, or 1073741824, but manufacturers of disks and memory chips like to mean 1000000000, as that makes their products look bigger on paper. And then some losses for the FAT. Depending on sector sizes etc. the FAT can eat different amounts of space. You can look for other formatting utilities, like others have already said. fat32fmt has served me well for other purposes but I honestly haven't tried it on flash memory. Also beware that using bigger block sizes will make the FAT smaller but less efficient if you store lots of small files. But if all you want is the Garmin .img file, then that's OK.

2) For my own part I tend to use "4G" cards so that I have some room for other goodies as well. The price difference these days is so small. If nothing else, I may have two maps on the same card and quick-switch between them by re-naming the directory (on a PC, naturally, but that's still a lot faster than copying the .img file). For example, the 2G internal space in my Nuvi550 is too small to fit all of the EU map so I've trimmed it down (with MapInstall) to Nordics plus nearby countries and then I have the rest of EU on a flash card. That's a lot smaller than 2G so it can fit alongside a larger map on a 4G card.

[talikarni]

As a PC tech, this is common among flash memory among lots of devices.

There are various situations going on here:
1) most manufacturers use a form of decimal which is 2GB (2000MB), yet the OS itself see it as binary aka 1,953 MB. When you also add in various formatting types with the card, it can vary and shave off a few hundred MB as well.

Coding Horror: Gigabyte: Decimal vs. Binary

2) Memory chip used for the storage. Some may use 2x 1GB chips, some 4x 512MB chips, others may have one 2GB chip. A single large chip should show the highest space available when used with a reasonable block size (see #3 below), and more smaller chips would show less total space. It also depends on if they used decimal or binary in their manufacturing process.

4x 512 or 2x 1024MB = 2048MB = ~1.88-2.0GB as seen by the OS.

2x 1000MB or 1x 2000MB = 1.80-1.86 GB as seen by the OS.

3) Block sizes used during the formatting can impact it as well. If larger blocks are used, that means less of the "left over" space is usable, which helps with access times. Smaller blocks can use more of the available space, but cause longer access times to the data since the files are in smaller pieces.

So say there are 4x 512MB chips using a 1024 block size. This means on each of the 4 chips, there is a large chunk of unused space due to the large block size. This may explain why one 2GB may show as 1.80GB.

If it uses one 2GB chip and smaller block sizes (say 256), this should show in the 1.9-1.95GB range.