Distribute This Page: Bookmark & Share Download: PDF Manual The iMac 'Core i5' 2.5 21.5-Inch Aluminum (Mid-2011) is powered by a Quad Core 2.5 GHz Intel 'Core i5' I5-2400S (Sandy Bridge) processor with a dedicated 256k level 2 cache for each core and a 6 MB shared level 3 cache. Apple Macintosh Instruction Manuals (User Guides) As per reader requests, direct links to official Apple Macintosh instruction manuals in PDF format - hosted by Apple's own support site- are provided below as well as on the specs page for each G3 and newer Mac.

Mac 21 Manual Free

Have a new Mac?

Learn how to set up your new Mac and discover features that let you do more than ever.

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Set up your new Mac

Use these basic setup steps to get your new Mac up and running.

How to move your content to a new Mac

Use Migration Assistant to copy all of your documents, apps, user accounts, and settings to a new Mac from another computer.

Use 4K displays, 5K displays, and Ultra HD TVs with your Mac

Learn about Mac support for 4K displays, 5K displays, and Ultra HD TVs. Also learn about the system requirements and how to set up and adjust the display or TV.

Get help with video issues on external displays connected to your Mac

Try these steps if the image on an external display connected to your Mac is blank or doesn't look the way you expect.

Connect an AirPrint printer to a Wi-Fi network

You can connect an AirPrint printer to a Wi-Fi network for wireless printing from your Mac, iPhone, iPad, or iPod touch.

If you can't print from your Mac or iOS device

If you can't get your printer to work with your Mac, iPhone, iPad, or iPod touch, these steps might help.

If your Mac doesn't connect to the Internet over Wi-Fi

If your Mac is set up to connect to a Wi-Fi network, it can analyze the connection for issues that affect its performance, including its connection to the Internet.

Use AirDrop on your Mac

With AirDrop, you can wirelessly send documents, photos, videos, websites, map locations, and more to a nearby iPhone, iPad, iPod touch, or Mac.

How to AirPlay video and mirror your device's screen

Use AirPlay to stream or share content from your Apple devices to your Apple TV or AirPlay 2-compatible smart TV. Stream a video. Share your photos. Or mirror exactly what's on your device's screen.

Using a Bluetooth mouse, keyboard, or trackpad with your Mac

Mac 21 Manual 2017

Learn about connecting Bluetooth input devices to your Mac, and get tips for using them.

Recharge the built-in battery in your Apple keyboard, mouse, or trackpad

Learn about charging the built-in battery of your Magic Keyboard, Magic Keyboard with Numeric Keypad, Magic Mouse 2, and Magic Trackpad 2.

If your Apple wireless mouse, keyboard, or trackpad isn't working as expected

Try these steps to fix issues with your Apple wireless mouse, keyboard, or trackpad.

iMac memory specifications

Learn about the types of random access memory (RAM) and video memory (VRAM) used in iMac computers.

Install memory in an iMac

Get memory specifications and learn how to install memory in iMac computers.

macOS Support

macOS is the operating system that comes with your Mac. Learn about and get help with apps, updates, services, and more.

Have a question? Ask everyone.

The members of our Apple Support Community can help answer your question. Or, if someone’s already asked, you can search for the best answer.

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