http://elinux.org/RPi_SD_cards#SD_card_performance.
There seems to be three tiers of read performance - 4MB/s, 11MB/s and 19MBs.
Some cards are very weak (Kingston SDHC 32GB class 10 = 4.7MB/s) and others are very strong (SanDisk Ultra II SDHC 4GB class 4 (15 MB/s) = 20.9MB/s). I take that to indicate that some manufactures are stamping lower 'Class' ratings on higher spec cards rather than acutally manufacturing lower performing parts.
MikeStatistics: Posted by hamster — Sat Nov 02, 2013 5:00 pm
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