SDHC Cards vs Hard Drive vs SSD

Tablet PC Review has an informative write-up on just how useful memory cards can be for laptop owners. They conducted some tests to see just how feasible it is to use an SDHC card as a "permanent" second drive, in comparison with more traditional storages such as hard disk drives and solid state drives (SSDs).

The products used for testing were the 8GB Transcend SDHC card and the 16GB A-DATA SDHC card. Both are"class 6" which means they offer the fastest read/write times currently available for SDHC cards. Used for comparison was a 128GB Memoright SSD (USD3,399) from DVNation, which proved so much faster, albeit it a tremendous price difference.

For the HDTune benchmark test, the SDHC cards were tested against a standard 2.5" SATA 60GB hard drive (5,400 rpm) and a 32GB Memoright SSD (USD999). Interestingly, the SDHC cards delivered access times similar to that of a SSD. This means the instant your computer needs to find data it is there. A caveat here is that some laptops use slow built-in card readers, meaning any SDHC card you use will run too slowly to be of any practical use as a second drive, even if it is a class 6.

The conclusion? Using a fast class 6 card like the 16GB A-DATA SDHC card in your laptops's built-in card reader can make an excellent second storage drive, but it isn't a great idea as a primary storage drive unless you don't have any other options.

The complete article, including a lucid explanation of "wear leveling" can be read here.