What Is The Maximum Sd Class One Can Benefit From?

[Grench]

Actually that is not true. Class 2, 4 and 6 SD cards do fit that convention, true. But "Class 10" is actually not a standard. It's just a marketing name given to really-high-speed cards by SD card makers.

It is more-or-less true. "Class 10" may not be officially blessed by the standard, but they're still following the conventions of the standard.

Or the SD Association does not update their website specifications list that we get to see. Remember, they charge for their official specs.

Important differences between the Speed Class and the traditional CD-ROM drive speed measurement ("×" speed ratings) are:

1. the ability of the host device to query the SD card for the speed class and determine the best location to store data that meets the performance required
2. class speed defines the minimum transfer speed.

Since the class rating is readable by devices, they can issue a warning to the user if the inserted card's reported rating falls below the application's minimum requirement.

On 21 May 2009, Panasonic announced new class 10 SDHC cards, claiming that this new class is "part of SD Card Specification Ver.3.0".[10] Toshiba also announced cards based on the new 3.0 spec[11] As of December 2009[update], the SD Association's Web site does not include information on this new class or new specification.

http://en.wikipedia.org/wiki/Secure_Digital

How many of us were using 802.11n for the last few years? It wasn't 'official' until October of last year.

 

[Awakening]

The class of a card IIRC only specifies minimum speed, that is the card's read (or is it write?) speed never goes below a specified speed for each class. Depending on the overall quality of a card the top speed varies much within each class. Looking at comparison charts and reviews are the only way to find out what cards are really good.

 

[WizardStan]

The class of a card IIRC only specifies minimum speed, that is the card's read (or is it write?) speed never goes below a specified speed for each class

The class is the speed the card guarantees it can maintain for extended write operations. Video and audio recorders, for example, need to have a guaranteed maintainable speed, otherwise the writes will fail. It is within the spec for a device to actually reject a card if the class isn't high enough for the application. Putting a class 2 (or probably even a class 4) into a video camera probably isn't going to cut it.

 

[mvickers03]

I have been having a problem with speed issues with my SD card (16gb class 6 Peak) copying a 700MB PSX ISO was taking over an hour to copy from my USB pen to the SD card. I thought I'd best replace the card before mentioning it so I ordered a new one.

The new card is a 16GB class 4 Kingston SD card and am amazed at the speed difference, my Pandora now copies the same file in less than 3 minutes.

I'm still not sure if the Peak card is Fake,Low quality, or just faulty, I'm guessing it's just low quality as I bought it from a retail store and does work fine, just very slow.

Anyway just though I'd throw that out there I would recommend avoiding Peak if at all possible

 

[emcp]

wow psx 700mb, i knew it a cd was this size
but i thought there be some compression

Also anyone reach a conclusion yet...............

 

[mvickers03]

Yupp 700MB for some games, now I know it's working nice I will buy a 32GB class 6 card and see how well that performs against the 16GB class 4.

I will let you know sometime soon

I can't see it getting much faster than 700MB in 3 mins though although I would love to be wrong.

 

[Qvazar]

Yupp 700MB for some games, now I know it's working nice I will buy a 32GB class 6 card and see how well that performs against the 16GB class 4.

I will let you know sometime soon

I can't see it getting much faster than 700MB in 3 mins though although I would love to be wrong.

700MB over 3 minutes is 3,9 MB/s, which matches the class 4 write speed rating.

A class 6 should give you at least 6MB/s write speed, a 50% increase; about 2 minutes for 700MB
A class 10 would take it down to max ~1 minute.

 

[mvickers03]

Wow. Thanks for the info! I can't believe the difference. that piece of crap Peak was so badly rated! I don't know how trading standards aren't on to it. I'm going to get a 32GB class 6 either this payday or next. I doubt I need a class 10 any time soon but that really would be awesome.

Also I'm sticking to major brands from now on. there was only a few quid difference in price but the major brand was out of stock.

LOL at Peak Hardware

 

[paulguy]

I plan to use a small class 10 sandisk extreme card as swap, so in case I run out of RAM, it won't lock up or chug (too badly) when swapping. Being small, it was cheap, so wearing it down won't be a big deal.

...I wanted to say more but I got distracted and lost my train of thought.

 

[WizardStan]

Folks, info please: a microSD through a SD adapter has any effect on read/write speeds? any difference at an actual SD one? Anyone tried?

Micro SD adapters don't do any logic, they're just a piece of plastic with lines running from the big pins to the little pins, one-to-one. The only reason a micro SD card in an adapter would be any slower than an actual SD card would be because the card itself is slower.