Review on High-Performance Samsung OWC 4.0GB PC3-10600 DDR3 1333MHz SO-DIMM Memory - Boost Your System's Speed and Efficiency by Travis Showcase

I edit a lot of photos, so I needed more storage than the 4GB that my 21.5-inch mid-2010 iMac had. I easily installed two of these 4GB memory cards on my iMac using the detailed instructions. (Click the apple icon in the upper-left corner, click About This Mac, click More Info to see the size and year of your computer, and the amount of memory installed. Then click the " icon Memory" to see if you have room to add more memory. In that box, click "Memory Upgrade Instructions", then click the type of iMac you recognized and you will find the type of custom memory and excellent installation instructions follow the instructions on the new cards be sure to ground your hands as recommended before touching new memory cards I was a little hesitant to try this but it was easy and I am glad I did I have 12GB of memory now and more If you want to be careful and methodical and need a faster computer I would recommend it.