• PC World
• »Components
• »Processors

Intel's first dual-core desktop processors are ready to ship, and our tests show they'll deliver some real benefit when you run software on them that's designed to take advantage of the two cores, or when you're performing multiple tasks simultaneously--running a virus check while surfing the Web, for instance.

As the name implies, dual-core processors incorporate two physical processors and two L2 memory caches into one piece of silicon, functioning, in theory, like two separate processors. Intel's first dual-core chip, the 3.2-GHz Pentium Extreme Edition 840 (which carries 1MB of L2 cache per core), goes one step further by including Intel's Hyper-Threading technology in each core, which theoretically brings you a "virtual" second processor per core.

Intel's chips are part of a wave of dual-core processing. AMD has already released its dual-core Opteron chips for workstations and servers, and its dual-core Athlon desktop CPUs are due at midyear. Unlike Intel's dual-core chips, the new AMD dual-core processors will not require new chip sets or motherboards, just a BIOS upgrade.

Like AMD's Athlon 64 chips and other new high-end Pentium EE chips, the dual-core CPU has 64-bit support. Other dual-core desktop processors from Intel's new Pentium D line will arrive in May; the Pentium Ds will use motherboards with the forthcoming 945 chip set. Dell has already announced its first system with the dual-core P4 EE 840 CPU: its Dell Dimension XPS Gen5 gaming and multimedia PC. Other vendors should also have systems available by the time you read this.

PC World tested a preproduction reference system from Intel with engineering samples of the P4 EE 840 and the new 955X Express chip set (it contained an 800-MHz frontside bus, but alternatively it can support a 1066-MHz bus); 1GB of DDR2-667 memory; and a Sapphire Radeon 850XT graphics card. The system ran Windows XP Professional.

The dual-core unit showed a slight improvement overall on WorldBench 5 versus the same system equipped with a 3.2-GHz P4 (both with Hyper-Threading on). However, it trailed the 3.73-GHz P4 EE configuration and the averages of four previously tested 2.2-GHz Athlon 64 3400+ PCs and of four 2.4-GHz Athlon 64 FX-53 systems (see chart below).

But the new system truly showed its mettle in certain portions of WorldBench 5--specifically our multitasking test and our media tests with Roxio VideoWave Movie Creator and Windows Media Encoder. Both applications are multithreaded, which means they can recognize and use the two cores as if they were two separate processors. On the multitasking test, the dual-core CPU produced its best result: It took just 9 minutes, 50 seconds to open numerous Web pages while converting video and music files to Windows Media format, whereas the single-core 3.2-GHz Pentium 4 took almost 12 minutes. It beat the Athlon systems' averages, too, and was a scant 9 seconds slower than the 3.73-GHz Pentium EE unit.

The dual-core PC also performed well in the Windows Media Encoder test, in which four WAV files and one AVI file are converted to Windows Media format: It shaved 49 seconds off the single-core 3.2-GHz P4's time of 6 minutes, 29 seconds, and essentially tied the 3.73-GHz P4 EE PC. In the VideoWave test, in which several AVI files are edited and converted to different video formats, the dual-core PC was 26 seconds faster than the 3.2-GHz P4 configuration (which took exactly 5 minutes) and 5 seconds slower than the 3.73-GHz P4 EE PC.

Interestingly, we found that the dual-core unit performed better on the multithreaded applications with Hyper-Threading turned off than with the technology enabled.

Not Tops Yet

Don't expect dual-core to be the top performer today for games and other demanding single-threaded applications, says Kevin Krewell, editor in chief of Microprocessor Report. But that will change as applications are rewritten. For example, by year's end, Unreal Tournament should have released a new game engine that takes advantage of dual-core processing, Krewell says.

Test Report: Dual-Core P4 Shines On Multitasking Test

Gains vary by test, but overall a system with Intel's Pentium Extreme Edition 840 CPU beats a same-speed single-core P4 machine.