AMD puts Barcelona quad-core into the spotlight at ISSCC

Posted by Wolfgang Gruener

San Francisco (CA) - AMD unwrapped a few more details about its upcoming quad-core server and workstation processor "Barcelona" at the International Solid State Circuits Conference (ISSCC). While the announcements focus on the power efficiency of the processor, the company tells conference attendees that it is confident about regaining the performance crown from Intel's Xeon 5300 series processors.

With a launch date that is believed to be scheduled towards the end of the second quarter of this year, AMD has begun to build momentum around its first quad-core processor, code-named "Barcelona." The new Opteron processor has the difficult task to stop the current freefall of dual-core Opteron average selling prices, put AMD back into a leadership position in the 2P server/workstation market and increase the firm's advantage in the 4P+ systems market.

Not unexpectedly, many of today's questions about Barcelona focus on the chip's performance capability. Typically, the real world performance of server processors heavily depends on the applications they run, but AMD says that customers will see dramatic improvements when compared to dual-core Opteron processors as well as Intel's quad-core Xeon 5300 ("Clovertown"). Opteron product manager Brent Kirby told TG Daily that Barcelona will outpace a dual-core Opteron by between 60 and 80% at any given clock speed. Compared to Intel's fastest Xeon 5300 (X5355), AMD promises that will be about 40% faster in some applications.

What makes Barcelona especially interesting is the fact that the processor will be offered in the same power envelopes as today's dual-core CPUs. Regular quad-cores will run at a thermal design power of 95 watts; "HE" versions will be rated at 68 watts and "SE" versions at 120 watts. Since Barcelona will use the socket F, companies can simply replace current socket F dual-core Opterons with the new processor, without having to worry about design or heat issues.

Intel's quad-core series is rated at a TDP of 80 watts for processors with clock speeds between 1.8 GHz and 2.33 GHz; the 2.66 GHz model is rated at 120 watts. AMD claims that the typical TDP of its processors will be about 15% lower than the TDP provided - which would put the lowest power quad-core at a typical power consumption of less than 58 watts.

Among the new power savings features is another generation of the firm's "PowerNow" technology. "Enhanced" PowerNow can dynamically adjust the voltage and clock speed of each processor core. Additionally, the processor is equipped with two separate power rails that enable Barcelona to reduce the frequency in the cores, but keep the memory controller running at full speed.

Shutting down parts of the processor that are not needed during certain periods of time plays an important role in the keeping the quad-cores thirst for power at a moderate level. AMD said that it has integrated "fine" and "course" clock gaters throughout the processor, which can either power down entire blocks or "increasingly" finer sections of the chip. There is also a new, platform-focused power management approach in the memory controller that can turn off the either the write or the read logic when not in use. AMD says this technique reduces the power consumption of the memory controller by up to 80% on "many" workloads.

AMD has not provided detailed specifications about the processor, but confirmed that Barcelona will integrate 2 MB of shared L3 cache as well as an improved virtualization feature that, according to AMD, can provide a performance gain of "up to 43% over non AMD-V driven applications."

Pricing of the processors remains unclear at this time. However the company mentioned during its recent Q4 conference call that it plans on introducing the quad-core at similar price levels that were covered by the first dual-core Opterons. Kirby told TG Daily that AMD intends to move Barcelona quickly into all segments of the server market.