iMac Early 2009

The iMac "Core 2 Duo" 2.66 20-Inch Aluminum (Early 2009) is equipped with a 2.66 GHz Intel "Core 2 Duo" processor, which has two independent cores on a single chip, a 6 MB shared level 2 cache, and a 1066 MHz system bus. It includes 2 GB of RAM (1066 MHz DDR3 SDRAM), a 320 GB (7200 RPM) hard drive, and a vertically-mounted slot-loading DVD±R DL "SuperDrive". The system features NVIDIA GeForce 9400M graphics that share 256 MB of memory with the main system, a built-in iSight video camera, and integrated stereo speakers beneath the 20" glossy TFT Active Matrix LCD (1680x1050 native) display.

Its connectivity suite consists of four USB 2.0 ports, a Firewire "800" port, built-in AirPort Extreme, and Gigabit Ethernet, plus a Mini DisplayPort for external display support in "extended desktop" mode.

The iMac "Core 2 Duo" (Early 2009) models closely resemble the "Early 2008" models they succeeded, sharing similar external enclosures—differentiated only by a "tapered foot"—and the same glass cover that "joins precisely to the aluminum enclosure creating a virtually seamless front surface."

While configurations and clock speeds are similar, several differences exist: the Firewire "400" port from the Early 2008 models was replaced by an extra USB 2.0 port, Mini-DVI was updated to Mini DisplayPort, and the 2009 models use DDR3 memory (instead of DDR2) with double the official capacity. They also feature enhanced graphics on higher-end configurations and shipped by default with a smaller keyboard lacking a numeric keypad.

This model was notably characterized by its switch to NVIDIA GeForce 9400M integrated graphics. While its graphics performance had pros and cons compared to the discrete GPUs of previous models, the overall system balance was considered good. The adoption of DDR3 memory and the change to a Mini DisplayPort signaled a shift towards a more modern architecture. The replacement of the Firewire 400 port with an additional USB port was met with mixed reviews, depending on user's peripherals. The new standard compact keyboard also symbolized Apple's move toward minimalism, though some users expressed a preference for a numeric keypad.