In the last two years, the x86 server market has been incredibly dynamic and competitive as Intel regained the performance lead from AMD with their Woodcrest MPU and then extended the lead with Clovertown, which is a pair of Woodcrest MPUs in a single package. While Woodcrest and Clovertown lead for traditional server workloads, AMD’s Opterons are still the processor of choice for most HPC and scientific workloads where huge data sets are a given and bandwidth is at a premium.
Earlier this year, AMD introduced Barcelona, their first quad-core product. Unfortunately, Barcelona was both later and at a lower frequency than many expected. Had AMD hit their targets (2.8GHz with 120W TDP, as the ISSCC paper indicated), it’s quite possible they might have a performance lead over Intel for more general server workloads. However, at the moment, it appears that AMD’s advantage is only for HPC – although they only trail Intel slightly for other workloads.
At the same time, Intel has been far from idle. Intel announced some general details of their 45nm process – specifically, that they had replaced the silicon dioxide gate dielectric with a high-K hafnium based material, and the gate electrode with an undisclosed metal. This practically eliminated gate leakage, and substantially reduced sub-threshold leakage (holding frequency constant).
Intel’s first 45nm products are destined for the server market – largely because it is both lucrative and relatively competitive. The notebook market is not particular competitive, and the desktop market is not lucrative. To reduce design risk, the Penryn core, which forms the basis of 45nm products, is a derivative of the Core microarchitecture. However, it is hardly a straight forward shrink of previous 65nm processors. Penryn has several modifications. The most notable is the larger 6MB L2 cache, but other improvements include a faster divider, a 1.6GHz front-side bus, new SSE4.1 instructions and a faster shuffle unit.
Intel’s 45nm server products are codenamed Harpertown (quad-core) and Wolfdale DP (dual-core). These MPUs are socket compatible with the previous generation, and can be used for upgrading any system with proper VRM support. Unfortunately, some board manufacturers and OEMs used less expensive VRMs, which do not support the newer generation.
While Harpertown is mostly drop-in compatible with the previous generation, Intel has designed a new workstation chipset that is specifically designed to complement Harpertown. The new platform is codenamed Stoakley and uses the Seaburg chipset (it’s amazing how many codenames Intel can pull out of a hat – far too many for a mere mortal to recall). This article provides an overview of the new Stoakley platform and a preview of performance, compared to the previous generation systems.