The iMac "Core i7" 3.5 27-Inch Aluminum (Late 2013) originally was offered as a "configure-to-order" configuration of the iMac "Core i5" 3.4 27-Inch Aluminum (Late 2013), but was sold as a standard configuration, too. Other than processor (and the corresponding level 3 cache), these two models can be identical.

The iMac "Core i7" 3.5 27-Inch Aluminum (Late 2013/Haswell) featured
a 22 nm "Haswell" Quad Core 3.5 GHz Intel "Core i7" (4771) processor with
four independent processor cores on a single chip,
an 8 MB shared level 3 cache,
8 GB of 1600 MHz DDR3 SDRAM (PC3-12800) installed in pairs (two 4 GB modules),
a 1 TB (7200 RPM) hard drive, and
a NVIDIA GeForce GTX 775M graphics processor with
2 GB of dedicated GDDR5 memory.

It also has a built-in "FaceTime HD" webcam and stereo speakers, but lacks an optical drive.

This model has a 27" 2560x1440 LED-backlit 16:9 widescreen IPS display with the "cover glass fully laminated to the LCD and anti-reflective coating."

The rear of the case is aluminum and is thicker in the middle and tapers to a razor thin 5 mm at the edges.

Connectivity includes
four USB 3.0 ports,
dual Thunderbolt ports,
Gigabit Ethernet,
802.11ac Wi-Fi (802.11a/b/g/n compatible), and
Bluetooth 4.0.

Compared to its predecessor, this model essentially has the same external enclosure, but it has a much more efficient "Fourth Generation" processor and architecture, as well as faster graphics, faster Wi-Fi, and the option of faster storage.

Please note that stock images are used.