These two chips are different inside and outside. The 1 MB cache Athlon 64 4000+ at 2.4 GHz (left) has 939 pins while these are part of the Intel socket LGA 775. The processor is rather bare today.

Although this shootout compares two entirely different platforms and literally compares apples and oranges, it represents what is available out there and shows how much energy each platform consumes. We picked five platforms for AMD's socket 939 and five others that support Intel's LGA socket 775 - and we did not do any performance testing this time.

AMD's Athlon 64 is a well-known and powerful specimen. We picked the 4000+ model at 2.4 GHz and 1 MB L2 cache memory. As the product name suggests, it is 64-bit capable and it supports Cool & Quiet for saving energy and reducing heat dissipation when ever possible by reducing the clock speed to 1 GHz. Intel ships the 500 and the 600 Pentium 4 series, while the latter is by far more interesting. These models come with 64 bit support (EM64T), 2 MB L2 cache and with an energy-saving feature called Enhanced SpeedStep. The 660 model runs at 3.6 GHz and steps down to 2.8 GHz.

AMD's Athlon 64 incorporates the memory controller and supports dual-channel DDR400 while Intel has to rely on the chipset's Northbridge. Here, dual channel DDR2 memory controllers for DDR2-533 and DDR2-667 are currently available. A special feature of all current Pentium 4 processors is Hyper Threading which fools the OS to believe there are two processors available. This is used to achieve a higher processor utilization and better system responsiveness with thread-optimized applications.