The Mac Pros also have new graphics cards: nVidia’s GeForce GT 120 with 512MB of dedicated video RAM. The Mac Pro's interior was redesigned to make accessing its internals and adding or upgrading components easier.
Configurations: The first Mac Pro has a quad-core 2.66GHz Intel Xeon 3500 processor, 3GB of RAM, and a 640GB hard drive. It costs $2499. (Get best current price.)
The second Mac Pro has two quad-core 2.26GHz Xeon 5500 processors, 6GB of RAM, and a 640GB hard drive for $3299.
The Mac Pros have a ton of build-to-order options. With the $2499 Mac Pro, you can get a 2.93GHz Intel Xeon 3500 processor for an additional $500. With the $3299 Mac Pro, you can opt for two quad-core 2.66GHz Xeon 5500 processors (for an additional $1400) or two quad-core 2.93GHz Xeon 5500 processors (for an additional $2600). You can add more RAM, up to the 16GB limit for either Mac Pro. Apple fills only one of the four hard-drive bays with the standard configurations, but gives you the option to add more drives and even configure them as a RAID. You can also add a second SuperDrive or upgrade the video card. A complete list of options is available on the Mac Pro tech specs Web page.
Performance: To no surprise, the Mac Pros are fast. Just to give you an idea of how fast they are, The Mac Pros more than doubled the Speedmark 6 score of a 2GHz Mac mini that shipped earlier this year. Interestingly, there’s not much of a difference between the two Mac Pros when comparing their Speedmark scores. That probably says more about the applications in our benchmark test suite than the Mac Pros themselves—few of the apps we test can take full advantage of four or more cores.
However, the 27-inch Core i5 iMac is just as fast as either Mac Pro. And if you swap the Core i5 iMac with the Core i5 processor, you'll have a machine that's actually faster than either Mac Pros and save some money.
Macworld’s buying advice: If all you care about is speed, get an Core i7 iMac, not a Mac Pro. The Mac Pro is good combination of speed and upgradability—you can add more internal hard drives, load a ton of RAM, or upgrade the video card. The $2499 Mac Pro is the place to start, and you might even want to add some of the build-to-order options, like more storage and more RAM. Consider the $3299 Mac Pro if your software can take advantage of the additional cores. However, with the Mac Pro, the smart move might be to wait until Apple releases new models with faster processors.
[Roman Loyola is a Macworld senior editor.]
[Editor's note: Updated 11/19/09 at 4:30PM with information about the Core i5 and i7 iMacs. Also updated the Mac Pro section, based on Core i5 iMac benchmarks.]