A speed test recently posted on Lloyd Chambers' Mac Performance Guide for Digital Photographers & Performance Addicts site compares an 8-core Mac Pro Nehalem 2.93GHz with a 4-core model running a faster 3.3-GHz processors. More is better, right? The results show that a serious gating factor for performance is in the software, not the hardware. Chambers says that software engineering matters. For example, only one of the Camera RAW converters tested – Phase One's CaptureONE 5 Pro — showed speed gains with the 8-core machine. While it didn't take advantage of all the processor's CPU power, it made better use of the extra cores, he said. Other conversion utilities were slower, such as Adobe Lightroon 2.7.
Most of the programs use multiple threads, but with disappointing efficiency; they just do not scale beyond a few threads. The inefficiency is not related to disk I/O, both by observation as well as having these tests run on the fastest possible internal disk setup. This lack of attention to efficiency is an engineering stupidity in today’s market of multi-core computers where time is money for many professionals.In the photo editing contest, only BenVista's Photozoom Pro 3.0.10 offered a speed gain with the 8-core processor. The software works stand-alone as well as a Automation plug-in and export plug-in for Adobe Photoshop. However, the architectural advantage of the 8-core machine becomes apparent for Photoshop when you throw RAM at it. The 8-core Mac Pro can handle 64GB of RAM. Check out the report, it's very interesting reading. In addition, Chambers suggests that digital photographers and professionals interested in buying a Mac Pro consider a refurbished machine. He offers a guide on the topic. However, few of the 4-core 3.3-GHz models become available.