24-inch iMac Core 2 Duo/2.16GHz

The most distinctive changes to the iMac line come on the outside -- the desktop now sports an aluminum enclosure that resembles what you might see from the Mac Pro or MacBook Pro. The 17-inch offerings are gone, replaced by a pair of 20-inch models and a 24-inch iMac, each with a glossy wide screen. Other changes are more modest -- the low-end iMac now runs on a 2GHz processor, instead of 1.83GHz. But all iMacs now feature a FireWire 800 port and can support up to 4GB of RAM.

Apple boosts the processor in its 20-inch iMac to 2.16GHz. And this isn't just a mere jump in clock speed -- the old Core Duo chip has been replaced with a next-generation Core 2 Duo that boosts the amount of shared L2 cache to 4MB. Other than the larger screen size, faster processor and bigger hard drive, the specs on this model match the 17-inch iMac Core 2 Duo/2GHz. Build-to-order options include a 2.33GHz Core 2 Duo processor and a 500GB hard drive.

Part of the iMac overhaul that added next-generation Core 2 Duo processors to the product line, this 17-inch configuration features a faster 2GHz chip than the 1.83GHz model; it also has more L2 cache as well as dedicated graphics. Instead of the Combo Drive you'll find in the 1.83GHz iMac, this 17-inch model comes with a DVD-burning SuperDrive. It also features built-in Bluetooth wireless networking capabilities in addition to the standard AirPort Extreme card. Finally, this model ships with 1GB of RAM installed; you can put as much as 3GB of memory in the system.

The iMac G5 is a computer completely built into a flat-panel monitor. This model, which has a 17-inch display and a 2.0GHz G5 processor, is in the middle of the line of the second iteration of the iMac G5, introduced in early May 2005. It includes a base of 512MB of RAM and built-in AirPort Extreme and Bluetooth 2.0.