Explanation: Symmetric Multi-processing boost

This characteristic is applicable to multi-core or multi-cpu systems only, and it shows how much (in terms of total processing power) the system gains versus a single-threaded application. So this is simply MT perf. divided by ST perf. and it is expressed in percents. Ideally, your system should get [Num threads] x 100 SMP boost, or probably with a few percents less because of inevitable management losses. This is not true for HT systems, where the boost is quite a bit less.