Multicore Processors are Faster and more Energy-Efficient

Go for Multicore Processors

Designers of processors, unlike PSU engineers, have been working to reduce power draw for years now. The Intel Core 2 Duo desktop processor, for example, is up to 40 percent faster and more than 40 percent more energy-efficient than its single-core predecessor. It optimizes power consumption by selectively powering up processor components only when necessary.

Intel claims that its Centrino Duo laptop technology is twice as fast as previous platforms, yet consumes 28 percent less power. Also very efficient are Intel's Pentium M and Celeron M processors and AMD's Turion 64 and dual-core Turion 64 X2.

Video cards remain energy hogs, however. High-end cards easily exceed 100 watts at full load, and popular dual-card setups for gaming double that wattage. Choosing a graphics card that fits your needs is key. If you don't play advanced 3D games, go with integrated graphics for the lowest power consumption.

You'll also want to evaluate a prospective PC's overall energy consumption by finding out how much electricity it draws when idle and at full power. Look for a desktop that uses 4 watts or less when in sleep mode, and 50 watts or less when idle. For laptops, the ideal is 2 watts or less in sleep mode, and 14 to 22 watts (or even less) in idle mode, depending on the graphics configuration.