Quote Originally Posted by memostothefuture
I thought I had purchased the second fastest card sandisk makes, which is why I am so confused




The Extreme III is a 30 MB/s non-UDMA, the Extreme IV is 45 MB/s UDMA, Extreme (with no Roman numerals) is 60 MB/s UDMA, and the Extreme Pro is 90 MB/s UDMA.


In general, the faster the card, the less likely to drop frames.


Whether you purchased the second fastest card Sandisk makes depends on when you bought the card. For example, the Extreme Pro was released right around the time that the 7D came out (Sept, 2009). The Extreme IV came out one year earlier, so the Extreme III was the second fastest card prior to Sept, 2008. But it seems that after releasing the Extreme IV, Sandisk changed their naming scheme, dropping the Roman numerals and simply going with Extreme (60 MB/s) and Extreme Pro (90 MB/s).