Complex sentence: Tera-Scale processors would improve energy efficiency by being able to "put to sleep" cores that are unneeded at the time while being able to improve performance by intelligently redistributing workloads to ensure an even workload spread across the chip.
Split into simpler sentences: Tera-scale processors would improve energy efficiency by being able to "put to sleep" cores that are unneeded at the time. The processors could then improve performance by intelligently redistributing workloads to ensure an even workload spread across the chip.