Apple iMac with 21.5" Display and 2.9GHz quad-core Intel Core i5 – Model# ME087LL/A

Core i5 and Core i7 Processors
The fourth-generation quad-core Intel Core i5 processor — based on the latest Haswell architecture — is standard on iMac. It's available at a clock speed of up to 3.4GHz. Or configure iMac with a quad-core Intel Core i7 at up to 3.5GHz. Since OS X is designed to take advantage of each core, iMac captures every bit of performance from the processor. OS X also supports Hyper-Threading in the Core i7, allowing two threads to run simultaneously on each core — giving you eight virtual cores of processing power.

Turbo Boost 2.0.
Say you’re using a processor-intensive application like Aperture or Final Cut Pro that benefits from extra power. Turbo Boost 2.0 automatically increases the speed of the active cores, so the Core i7, for example, can offer up to 3.9GHz. And by shifting core frequency in small increments, Turbo Boost allows the processor to manage performance without sacrificing efficiency. All this takes place behind the scenes, so your work — and play — goes smoother and faster.

iMac graphics have gotten even more powerful across the board. NVIDIA GeForce 700 series graphics processors are faster than the previous generation and include double the video memory. That translates into more frames per second, smoother animation, and better responsiveness when you’re using graphics-intensive apps like 3D games, high-resolution photo and video editors, and more.

If you choose the NVIDIA GeForce GTX 780M with 4GB of video memory on the 27-inch iMac, you get the best graphics performance available in an all-in-one computer. And if you go with the 2.7GHz iMac, it comes with integrated Intel Iris Pro, which delivers discrete graphics-level performance.

With three-stream 802.11ac technology, iMac takes desktop Wi-Fi speeds over the top. When it’s connected to an 802.11ac base station — including the new AirPort Extreme and AirPort Time Capsule — you can reach data rates of up to 1.3Gbps. That’s triple the previous 802.11n standard, which means you’ll get up to three times faster Wi-Fi. You also get double the channel bandwidth, with 80MHz-wide channels providing more room for more data to flow faster than ever.

With one tiny port, you get superfast data transfer speeds and huge expansion capabilities. Thunderbolt features two 10-Gbps data channels per port, which means data transfer is up to twice as fast as USB 3.0 and up to 12 times faster than FireWire 800. And don’t worry about a single drive or peripheral tying up a Thunderbolt port: you can daisy-chain as many as six devices plus a display. All iMac models include two Thunderbolt ports for even more expansion possibilities.

Storage
1TB hard drives are now standard across the entire iMac line. You can maximize your storage by configuring the 27-inch iMac with a drive up to 3TB in capacity. Or choose up to 1TB of flash storage (up to 512GB on the 21.5-inch model). For the best of both worlds, choose the Fusion Drive option in 1TB or 3TB capacities.

Memory
The 21.5-inch iMac comes with 8GB of memory and can be configured online with 16GB. On the 27-inch iMac, 8GB of memory comes standard, and you can upgrade to 16GB or 32GB. Configure and buy your iMac at the Apple Online Store and it will arrive with the memory already installed. Or add more memory to the 27-inch model yourself by popping open the easy-to-access memory panel on the back.