add SSD hard drive

Depends on your exact model. Your device ID is very generic.

All but the entry-level iMac "Core i5" 2.5 21.5" model could be custom configured with an SSD at the time of purchase in addition to a hard drive. With some effort, an SSD can be installed after purchase in these models as well.

For the secondary SSD in the "Mid-2011" 27-Inch models, OWC provides this helpful step-by-step video of the challenging disassembly and upgrade process by watching the video, you should have a good idea about whether or not you feel comfortable performing the upgrade yourself or if you would prefer to hire a professional.

If you choose to DIY purchase all the recommended tools from the appropriate guide. Study the guide and notes (not just look at them) before you begin. You will want to label and separate all the screws, and know in advance if a connector is a ribbon cable with a lock or a press connector so you do not tear connectors off the logic board.

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