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Hello everyone! I ordered 2 RAM plates (4GB each) that are compatible for my iMac and installed them carefully into the empty slots. I had 2 RAM plates already installed on my iMac 2GB each. My RAM plates are DDR3 1333 Mhz which I checked when I bought the new ones. My Mac only shuts down randomly when I work on things that are hard to process so its hard for me to tell why it does that. it has shut down 3 times since I started writing this question :( Please help!
RAM Type:PC3-10600 DDR3Min. RAM Speed:1333 MHz Details:Supports 1333 MHz PC3-10600 DDR3 SO-DIMMs (204-pin). Try putting the old RAM in and see if the problem persists.