MobileTechReview.com logo
MobileTechReview News, Reviews and Forums
Phone Notebooks & Tablets Gaming Gadgets iPhone & iPad Video Reviews


General Discussions >> Ask Us!

Pages: 1
carlzzz
junior member


Reged: 02/04/08
Posts: 1
SD speed: class vs. X rating
      #29562 - 02/04/08 11:39 PM

Trying to compare the speed of SD cards. When the SD card says 50X, 100X, 133X, etc. what is X?

I understand that only SDHC cards are rated by class, and that class may be calculated differently than the X speed rating. Is there any general speed estimate for the classes?

Is there any way to generalize and compare the speed of SD cards rated with X and SDHC cards rated with class?

Carl


Post Extras: Print Post   Remind Me!   Notify Moderator  
LisaGModerator
Head Honcho
****

Reged: 07/11/02
Posts: 8263
Loc: Texas
Re: SD speed: class vs. X rating [Re: carlzzz]
      #29567 - 02/05/08 08:19 PM

Unfortunately, there is no standardization as to what the "x" rating means across brands of cards. Kingston states that "x" refers to write speed, where x= 150 KB/sec, so their 120x card has an 18 MB/sec. transfer speed. But other manufacturers don't necessarily use the same formula.

With SDHC cards, the class rating doesn't have a translation to that mystery x value in non-HC cards. But the higher the class, the faster the card-- and there are at least specs for classification of cards by class .

--------------------
Lisa Gade
Editor in Chief, MobileTechReview


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1



Extra information
0 registered and 3 anonymous users are browsing this forum.

Moderator:  Greg, LisaG, Jacob_Spindel, Tong Zhang 

Print Topic

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled

Rating:
Topic views: 5212

Rate this topic

Jump to

Contact the Folks at MobileTechReview.com | Privacy statement Go to mobiletechreview.com homepage

Powered by UBB.threads™ 6.5.5