A closer look at Apple\'s new iMac Core Duo

In addition to being the first of Apple Computer's personal computer offerings to make the transition to Intel microprocessors, the new iMac Core Duo also sports a plethora of architectural and technological changes, which sources have began detailing to AppleInsider.

For starters, the iMac Core Duo uses a Low Voltage Differential Signaling (LVDS) interface — a low noise, low power, low amplitude method for high-speed data transfer — for transmitting data to the computer's 17- or 20- inch LCD display.

Though the new iMac looks remarkably similar to the iMac G5 with iSight announced late last year, one way to differentiate the two models is to look for the presence of a mini-DVI output port featured only on the iMac Core Duo. This new DVI out port will allow users to choose between video mirroring or extended desktop (with an added Apple DVI Display Adapter).

The iMac Core Duo is reportedly the first iMac to support Apple's extended desktop feature, which lets users extend their viewing capabilities by using two or more displays at the same time. With this functionality, users can choose to view a single document or application across multiple displays, or use each display to view a different document or application.

Like the previous iMac, the iMac Core Duo sports a built in iSight, which sources say uses a CMOS sensor with a fixed-focus plastic lens rather than a CCD sensor with automatic focus like the one used in Apple's stand-alone iSight product.

Sources also report that support for AirPort Extreme and Bluetooth in the new iMacs is achieved through separate cards instead of a single a combo card used by Apple in the past. Antennas for the wireless technologies are mounted at the top of the iMac enclosure — the Bluetooth one on the left side and AirPort Extreme on the right.

True to reports making the rounds on the Web, the first Intel Macs use EFI (Extensible Firmware Interface) — essentially an updated BIOS specification that allows vendors to create operating-system-independent device drivers that are stored within the hardware itself. The EFI BIOS is also used to select and load the operating system when the computers first starts up.

The iMac Core Duo's Boot Manager — accessible by holding the option key at startup — also features some slight interface improvements, sources say, but for the most part remains visually unpleasant. The systems also include a NVRAM (Non-Volatile RAM) as opposed to a PRAM (Parameter RAM) and a SMC (System Management Control) as opposed to a PMU (Power Management Unit). The NVRAM is still resettable by using the Command-Option-P-R key combo.

Each new iMac Core Duo appears to be shipping with Mac OS X 10.4.4 for Intel build 8G1165, which does not include support for the Mac OS 9 Classic environment.