The dual-core Opteron chips will be about the same size and produce the same
amount of waste heat as current single-core Opterons. The new chips will fit
into the existing server designs. Single-core Opterons have 106 million
transistors, while the dual-core model has 205 million transistors, based on a
90-nm process and SOI technology.

Each core has its own 1MB section of high-speed cache memory. The processor
design also consists of hardware pre-fetch enhancements. It also has 10 new SSE3
instructions. It also includes four write combing buffers and power savings
features in the C1/C2/C3 states. The dual-core models run 600MHz to 1GHz slower
than the single-core models to prevent overheating problems.

Future versions of the dual-core Opterons/Athlon 64s may contain two or more
memory controllers to keep the processors fed with instructions. The problem is
that processor speeds have outpaced memory clock speeds, meaning that the
processor can be forced to wait for the rest of the system to keep up. To solve
the problem, processors like Intel’s Montecito have added massive amounts of
level -2 and level-3 cache to store frequently-used data close to the processor.

A two-processor dual-core system clocked 5 clock speeds down from AMD’s
fastest part will generate performance of approximately 125 to 140 percent
performance of the dual-processor unicore system. A dual-core, dual-processor
system clocked at only three grades slower than the fastest AMD chip will
perform at between 130 to 160 percent of the performance of the base system.

Future versions of the dual-core Opterons/Athlon 64s may contain two or more
memory controllers to keep the processors fed with instructions. The problem is
that processor speeds have outpaced memory clock speeds, meaning that the
processor can be forced to wait for the rest of the system to keep up. To solve
the problem, processors like Intel’s Montecito have added massive amounts of
level -2 and level-3 cache to store frequently-used data close to the processor.

“The dual-core part is in our labs and will be sampling soon,” McGrath said.
The company expects to introduce dual-core chips for the one- to eight-socket
server and workstation market in mid-2005. Dual-core processors for the client
market are expected to follow beginning in the second half of 2005, according to
a presentation by the company.