Know Your Processors: Intel Core and Xeon20 Nov, 2014 By: Alex Herrera
Herrera on Hardware: A primer on workstation CPUs for CAD.
Xeon and Core — you know the names, but what's the real difference between the two workstation CPU families from Intel? Which is the right choice to power your particular CAD workflow? Which offers the features, performance, and price point that best meet your needs?
Intel offerings are the only CPU choices available for professional workstation customers. Intel and AMD have long held a duopoly in the market for CPUs in mainstream consumer and corporate PCs, but the same is not true in the workstation market. After a promising surge a decade ago, AMD's CPUs are, for all intents and purposes, absent from workstation platforms today.
Workstations are Intel's game for now, with the company pitching two lines of CPU products that are suited to CAD applications: Core and Xeon. The two share a common foundation in processor technology but have been shaped for different users and applications. Each offers its own balance of performance, reliability, expansion, and cost to meet the needs of a broad range of client and server computing platforms, including the mobile and desktop workstations that today's CAD professionals rely on.
Mainstream corporate and consumer PCs form the primary market for Core, while servers (multisocket servers in particular) form the primary market for Xeon. Workstations are uniquely situated in Intel's product map — at the crossroads of the two CPU brands.
Core drives mobile workstations virtually on its own, whereas Xeon currently commands the lion's share of CPUs sold in traditional, desktop workstations. Core processors reside in about one-third of all branded desktop workstations, typically those with more modest hardware configurations and commensurately lower price tags. The remaining two-thirds, including all dual-socket workstations, ship with Xeon.
Nearly half of all desktop workstations in Q1 2014 shipped with Intel Xeon processors, according to Jon Peddie Research.
The Core family of CPUs delivers uncompromised single-thread performance, while also providing users and applications the opportunity to leverage multiple processing cores. Single-thread performance, which uses one serial path of execution, remains an important avenue that Intel continues to push forward with each new generation. It must, because while the software industry continues to expand its emphasis on multithreading (multiple, concurrent execution paths), the truth is that for many computing tasks, such as the parametric modeling ubiquitous in CAD workflows, fast, single-threaded execution still matters.
With each generation of its CPU microarchitecture, including its new fourth-generation Core (codenamed Haswell), Intel has been populating multiple execution cores per processor to raise multithreaded performance. But it's also incorporating features designed to speed single-threaded code, such as Turbo Boost 2.0, Advanced Vendor Extensions (AVX), and Hyper-Threading.
Turbo Boost 2.0 determines how to allocate the chip's power budget across on-chip resources, temporarily overdriving core clocks when demand is high and as thermal budgets allow. AVX accelerates processing when performing the same arithmetic and logic operations across multiple pieces of data, a vector operation common in applications from simulation to rendering. Hyper-Threading technology, which has evolved over the years, allows each physical core to manage two concurrent execution thread contexts, executing the two in parallel when shared resources allow.
Beyond these trademarked features, Intel continues to periodically augment resources within existing microarchitecture instruction and data pipelines. These improvements include adding execution units, deepening buffers, and improving branch prediction. By combining resource expansion, pipeline tuning, and new features such as Turbo Boost, the micro-architecture forming the basis of both Core and Xeon processors continues to deliver excellent single-thread performance, with a cost-effective balance of multicore capabilities to boot.
Xeon: Biggest Bang
Core offers capable CPUs for high-performance desktops and entry-class workstations, but Xeon pushes beyond. Intel's premier brand strives to deliver more of what workstation buyers value: reliability, compatibility, and CPU horsepower. In general, Xeon offers all that Core does, plus the following:
- Higher core counts per processor
- More memory cache per processor (usually)
- Support for dual-socket configurations (Xeon E5), providing higher performance through more processing cores, more memory, and more system bandwidth
- ECC (error-correcting code) memory support.