Good Deals
The systems we looked at for this review can't compete with costly, decked-out high-end models, but they do provide a great package for your money. All six had at least 250GB of storage, with two offering striped RAID arrays. All had double-layer DVD burners and, in three cases, a DVD-ROM drive as well. CyberPower's gaming machine even had SLI graphics, in the form of twin eVGA e-GeForce 7600 GT cards. Not surprisingly, it was the top performer on our gaming tests.
Polywell's MiniBox 939NP-4200, which used a 2.2-GHz Athlon 64 X2 4200+ processor, turned in the best performance of the group, with a WorldBench 5 score of 110. That's fast, but far from the speediest system we've tested (the $4199 Xi Computer MTower 64 AGL-SLI, a machine on our Top 10 Power Desktops chart with a 2.6-GHz Athlon 64 X2 FX-60 CPU, scored 142).
For details on each machine, see the full reviews linked below.
In reviewing the test results, we noted that at this price point the Intel-based machines closely matched the AMD-powered systems in performance. The two companies' dual-core processors are still quite different, though; for more information about the varying architecture, see "Dueling Dual-Core CPU Architectures." For this story we also examined a dual-core iMac, and we report our findings in "Core Duo-Based iMac Packs Lots of Power." Finally, to find out how the technology is affecting mobile PCs, we looked at a dual-core laptop; turn to "Notebooks Get a Boost From Dual-Core Processors" for more on how portables are changing.
Under the Hood: Dueling Dual-Core CPU Architectures
Our current crop of value desktops contain dual-core processors from AMD and Intel. However, while they share the dual-core moniker, the two companies' desktop CPUs are very different.
From the ground up, AMD designed its Athlon 64 X2 and FX-60 desktop processors to include two cores. Intel created its Pentium Extreme Edition and Pentium D desktop CPUs by putting two single-core chips in one package.
Intel beat AMD to the dual-core desktop punch in April 2005 by assembling the first two-core x86 processor--the Pentium Processor Extreme Edition 840--out of existing parts. Engineers put two 3.2-GHz Pentium 4 cores on the same die (each with its own 1MB Level 2 cache), and then connected them with an external 800-MHz frontside bus.
To boost performance, Intel left in the Pentium 4's hyperthreading technology, which makes the operating system see each chip as two. To create the subsequent, lower-priced Pentium D processor (launched in May 2005), the company employed cores running at slower speeds and turned off the hyperthreading. In January 2006 Intel introduced updated dual-core Pentium D chips based on smaller, faster cores.
AMD rolled out its first dual-core CPUs in April 2005 under the Opteron name for servers and workstations, and then launched its Athlon 64 X2 desktop chip a month later. One of the clearest advantages of AMD's design is the ability of the two cores to communicate with each other within the die so that data doesn't have to travel over a slow external system bus as in Intel's arrangement. Each core gets a 512KB or 1MB L2 cache.
Evaluating the performance of CPUs that use different chip sets is an imperfect science. But in the vast majority of our tests of PCs using comparable processors, AMD's dual-core architecture has proved to be the superior performer.
Both companies have new CPUs on the way. AMD recently launched versions of its X2 and FX processors based on its new AM2 socket, which supports faster DDR2 memory. And Intel is poised to debut its next-generation CPU, called the Core Duo 2, later this year (the first Core Duo was a mobile processor). Based on a new architecture, the desktop Core Duo 2 has exhibited strong performance in early public tests.
Tom Mainelli What About Apple? Core Duo-Based iMac Packs Lots of Power
Robert Cardin; Background: Geoff SpearDual-core technology isn't exclusive to PCs--Apple has gotten in on the action, too. The company introduced dual-core technology on the iMac last February. And with the addition of Intel processors and Boot Camp for running Windows, it's now possible for us to see how Macs compare with Windows-based PCs. To determine what kind of power an iMac can provide, we examined the 20-inch wide-screen model, an all-in-one system that's among the most elegant computers you can buy.
When you gaze at the iMac's gorgeous screen, all the other hardware seems like an afterthought, because all the components are neatly tucked away behind the LCD. The list price for the model we tested, with 1GB of RAM, is $1799, somewhat above our ceiling, but Apple also offers a 15-inch unit that starts at $1299.
The iMac uses a 2-GHz Core Duo T2500 processor, Intel's mobile dual-core CPU, which enables this thin system to run cool. It earned a score of 96 in our WorldBench 5 tests, making it plenty fast for a value system. The iMac also completed our multitasking tests quickly, ahead of the value PCs that we reviewed for this roundup.
The system offers solid 3D graphics, thanks to its ATI Radeon X1600 card with 128MB of RAM, but one drawback is that Macs running Boot Camp conflict with the 3DS Max portion of our WorldBench 5 tests, and as a result the iMac was unable to complete the gaming portion of our testing. The wide-aspect display looks terrific at its native 1680 by 1050 resolution, and the system can support external monitors at up to 1920 by 1200 (digi