Across government, these workhorses power everything from mission-critical financial models to NASA research projects and military simulations, such as one the Army uses to replicate airports in Iraq and Afghanistan so pilots preparing for their first flights to those areas reduce the chances of mistakes.

High-end desktop PCs are following the same price and performance trends that make their lower-end counterparts more affordable. Nevertheless, top-notch performance still requires a significant investment, often ranging from $2,000 for economy models to at least $6,000 for more powerful systems.

In addition to cost considerations, PC buyers must also weigh the wide range of new choices for core components. “Our research shows a lot of technologies at almost every component level are at important inflection points in the high end of the market, starting with the microprocessor,” said Addison Snell, research director of high-performance computing at IDC, a market research firm.

The key to building the right system in this environment is to focus on six areas, experts say.

1. Processing muscle
Dual-core microprocessors, tandem CPUs fused together into a single chipset, are becoming commonplace in high-end applications. Unfortunately, their cutting-edge engineering and price premiums don’t guarantee a speed boost over single-core processors.

For example, the price difference of a single Advanced Micro Devices Opteron 244 chip and a dual Opteron 244 processor is about $200. But the top-end dual Opteron 240EE jumps to $900 more than the single processor.

A justifiable performance gain only comes if the dual chips run software that divides large processing tasks into separate smaller jobs, a process known as multithreading. Commercial software vendors and developers of custom government applications are still in the process of converting software for this capability.