Intel Dual Core
In spite of the fact that AMD was the first to announce development of its dual core CPU, Intel was first to the market with its dual core Pentium Extreme Edition 840 CPU. This processor, like AMD’s first Athlon dual core, was manufactured with a 90 nm fabrication process that had some heat and power concerns, but offered incredible computing power for the desktop. The architecture of this CPU differed from the first dual core Athlon’s in that it required an external memory controller. Also, the cores of the Extreme Edition 840 communicated with each other through the relatively slow Front Side Bus.
Although this CPU fit the same LGA775 socket as its Pentium 4 counterparts, they were not a drop in replacement for the older Pentium 4 chips because the new CPU required a new chipset. This forced the purchase of new motherboards by customers desiring the new technology, slowed adoption of the Intel dual core processors, and set the stage for AMD to make a strong showing when its Athlon 64 dual core CPUs finally came out. Intel’s dual core CPUs were fitted with a shared 2 MB L2 cache that gave it an advantage over AMD’s offering that had a smaller, dedicated cache for each core. The shared cache was not only larger on a per core basis than AMD’s Athlon dual core, but also was accessible by each core, enhancing the CPU’s performance with single threaded applications.
AMD Athlon Dual Core
AMD’s late appearance to the dual core desktop CPU market was in spite of its foresight to design the Athlon 64 with space for a second core. When development was finally complete, the move to production was relatively smooth because the manufacturing processes were already in place. AMD released the dual core Athlon 64 X2 to work in existing AM2 socket motherboards, giving an advantage to Athlon 64 users wishing to upgrade. This helped AMD overcome the disadvantage of being the last to market.
The Athlon X2 was created with two Athlon 64 CPUs on the same die together with a shared memory controller and HyperTransport technology bus (AMD’s high speed, full duplex answer to Intel’s half duplex Front Side Bus) on the CPU die. While HyperTransport presented an advantage, the memory controller shared between the cores proved to be a limiting factor. Another detraction of AMD’s design was the small, dedicated L2 cache for each core rather than the more efficient shared L2 configuration utilized by Intel.
Which CPU Won?
Who won the battle of AMD Athlon dual core vs Intel dual core? The winner is in the eye of the beholder: while Intel edged out AMD in overall performance, AMD was quite impressive and made dual core technology available at a lower cost.