32gb MicroSD?

Delbert Franz ddf at sonic.net
Thu Oct 13 19:51:59 EDT 2011


On Friday 09 September 2011, James Haggerty wrote:
> Hi all,
> 
> Now these are becoming available at decent speeds, has anyone tried
> them in the Nanonote?
> 
> Thanks,
> James.
> 
> _______________________________________________
> Qi Hardware Discussion List
> Mail to list (members only): discussion at lists.en.qi-hardware.com
> Subscribe or Unsubscribe: http://lists.en.qi-hardware.com/mailman/listinfo/discussion
> 
> 

I just finished configuring a 32gb microSD card from Transcend.  Here 
is the description from the Newegg order confirmation: 

FLASH 32G|TRANSCEND TS32GUSDHC4 R

There can be variations in such cards, even with the same capacity and 
from the same maker:)  This card works in the Ben.

This is a Cat 4 card and in writing to it on my desktop, the top write 
speed was just over 4 MB/sec.  The average speed when copying about 9 
GB of data to one of my partitions was about 2.5 MB/sec.  Finally 
copying the root of about 480 MB showed an average rate of transfer of 
about 1.5 MB/sec.  

I'm not sure the Ben CPU is able to even put out 4 MB/sec on writes.  
A quick run of Bonnie with the default output size of about 100 MB, 
shows sequential character output at about 2.5 MB/sec and sequential 
block output at about 3.1 MB/sec.  This is on an ext4 filesystem with 
a size of about 27 GB.  

Sequential character read was about 4.4 MB/sec and sequential block 
read was about 8 MB/sec.  

I make the preliminary judgement that a higher category card would
not result in increased speeds.  The read and write times on the Ben
are quite a bit less than when using my desktop.  It then seems
that it is the Ben's power that places the limit on the transfer
speed and not the card.  

Hope this helps.  The retail cost of the card was about $45 US.

                        Delbert





More information about the discussion mailing list


interactive