Apple has upgraded is Mac Pro desktop with a pair of 3GHz quad-core Intel Xeon processors, less than a month after a website cock-up revealed such a machine was in the offering. However, it doesn't come cheap. In its default configuration with dual 3GHz quad-core Xeons and 2GB of RAM, the Mac Pro costs a hefty $4,296. Users can max out the system by outfitting it with 16GB of DDR2-667 FB-DIMMs, 3TB of storage via four 750GB hard drives, an Nvidia Quadro FX 4500 professional graphics card, dual 16X DVD burners, 802.11n Wi-Fi, quad-channel 4Gb fiber channel PCIe cards, and other extras. At that point, the machine will set you back almost $15,000-and that's without a monitor! Ouch! But check out this speed comparison :-)