SDHC speed

Here is a non-scientific test of my SD/SDHC cards. The test was, to write 70MB of a Java folder from the C: drive to the root folder of a memory card connected to a USB2.0 port, disconnect the memory card, reconnect the card, then transfer the Java folder from the memory card back to a temporary folder on the C: drive.

Patriot 4GB SDHC (Class 6)

Writing to the card: 90 seconds
Reading from the card: 30 seconds

HP 8GB SDHC (Class 4)

Writing to the card: 80 seconds
Reading from the card: 28 seconds

Kingston 2GB SD

Writing to the card: 105 seconds
Reading from the card: 26 seconds

Foto Source 1GB SD

Writing to the card: 75 seconds
Reading from the card: 27 seconds


The fastest overall of the bunch is this Foto Source 1GB SD card bundled with the Nikon D80 when I purchased it. It was not really part of the package but the store just threw it in. It's a no name brand. The new 8GB SDHC comes next, followed by my first SDHC card, the 4GB SDHC, and then the Kingston 2GB SD. The 8GB SDHC is a Class 4 SDHC (this Class specifies a minimum speed of 4x, i.e. 4 x 150 kBps or 600 kBps). It performs better than expected at about 1.1 MBps. The Class 6 Patriot 4GB SDHC card is expected to write at a minimum 900kBps. Well, it writes at over 1.2 MBps.

I thought the Kingston 2GB SD was really fast, from what I could see when viewing pictures off the card but when sustained writes are performed, it does not measure up very well. The specs of it are: up to 5 MBps reads and 1.5 MBps writes. It does not appear to perform anywhere close to specs on sustained I/O. Sustained reads and writes took more than twice longer than expected. Very disappointing.

Regardless of the speed, there is absolutely no problems with using any of these SD or SDHC cards in a D80 for continuous shooting. Remember that the D80 has a internal write buffer.