Computing in a Parallel Universe

Multicore chips could bring about the biggest change in computing since the microprocessor. By Brian Hayes. The pace of change in computer technology can be breathtaking—and sometimes infuriating. You bring home a new computer, and before you can get it plugged in you're hearing rumors of a faster and cheaper model. In the 30 years since the microprocessor first came on the scene, computer clock speeds have increased by a factor of a thousand (from a few megahertz to a few gigahertz) and memory capacity has grown even more (from kilobytes to gigabytes). Through all this frenzy of upgrades and speed bumps, one aspect of computer hardware has remained stubbornly resistant to change. Until recently, that new computer you brought home surely had only one CPU, or central processing unit—the computer-within-the-computer where programs are executed and calculations are performed.