This caused some confusion for me, so I wanted to share with everyone. Observation While ripping some DVDs using HandBrake, I realized my mac was using a lot of system resources. I opened up Activity Monitor, and much to my surprise, the % CPU being used by HandBrake was ranging from 340 to 390 (!). How was this possible? note: Core i7 processor, dual core 13 inch What I think is the Answer The i7 in this laptop is dual core, and has hyperthreading enabled. This means that the computer can operate as if there were 4 cores. The process HandBrake is making full use of the hyperthreading (in fact, it displays at 24 threads) and is therefore maximizing the use of the processor. Since up to 4 virtual cores can be maintained, the maximum % CPU usage is 400, not 100. Can anyone with a more extensive knowledge of the subject confirm this?