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SD memory card Speed Class system doesn’t work, admits SanDisk

Top memory card manufacturer SanDisk has said that the Class system, which indicates the speed of an SD memory card, no longer works.

SanDisk product marketing manager Ruben Dennenwaldt admitted that “95 per cent of people don’t know what [the SD Speed Class system] means.”

He says that in today’s memory card market, it “doesn’t really make sense at all”, and that “it’s our own fault that we introduced this class system together with the SD association.”

The Speed Class rating tops out at Class 10, which means the card can maintain a write speed of 10MB/sec.

Today’s top memory cards far outstrip this level of performance, with SanDisk’s own top-end Extreme Pro range capable of speed of up to 90MB/sec.  

Dennenwaldt says that rather than seeking out a new ‘modernised’ card rating system, “what’s important is… messaging on naming what the highest possible speed” of a card”.

As the speed of SD storage improves, the Class system is becoming increasing redundant, with only low-end memory cards fractionally less expensive than faster ones failing to reach the ‘Class 10′ standard.

SD cards are by far the most common type seen in electronic devices to date – Dennenwaldt sees microSD, SD and Compact Flash as the three key “form factors” of memory card storage that won’t be challenged “over the next 2, 3, 4 years.”

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