sandisk Extreme 60MB/s write speed droped below 30MB/s......

[ph2007]

Hi guys,

I have been using a 32GB sandisk Extreme 60MB/s (rated 40MB/s write speed)
the speed is very consistent on this card, always run @37-39MB/s when i doing RAW on my 6D.

recently I bought another 3x of the same card..... guess what?
All of it only run @27MB/s...... how is it possible? (cut my RAW duration almost half...... /sign!)
anyone have this problems?

[Walter Schulz]

Insert them into cardreader and run benchmark. Is data write performance in sequential mode below rated speed?
Yes -> Contact seller, maybe faked cards.
No -> Check file system used.

[ph2007]

my usb2.0 card reader maxed out 20MB/s
can't do benchmark@@

[Walter Schulz]

Take 20 bucks, get a decent USB 3.0 cardreader (Kingston FCR-HS4 or else, see Camera Memory Speed. If your PC doesn't have USB 3.0 interfaces: Get an interface card.