I was suprised today.
I've read the parasolid modeling engine is multi-threaded which means it supports multiple processors or in my case a dual-core processor. Normally my task manager is running at 50% because most of what Solidworks does is linear and not multi-threaded. In the model I'm working on I'm modifying it by using the delete face and move face functions in Solidworks. These functions must be multi-threaded in parasolid because both CPU's were running at 100%.
I am running an Athlon 64 X2 Dual core Processor 4600+ @ 2.41 GHZ.