The main Benefits of IncrediBuild for Build Servers are the following: 

1. With IncrediBuild installed on other machines, the build server power is dramatically increased since it can use more cores for the build process by harnessing idle CPU cores on other machines in the network no matter if the build is done with Continuous Integration or gated check-in. In addition, due to IncrediBuild's way of parallelizing tasks, many more tasks can be utilized and performed in parallel, which drastically reduces the build time.
2. IncrediBuild offers a graphic interface which provides an easy build process view and various build related information which allows you to  detect problems, such as bottle necks and environmental issues that might affect the build.
3. Batch Build option that allows various configurations to be built at the same time, rich command line interface, etc... 

It is important to note that IncrediBuild has a scalability advantage since when it is installed on the developers machines, each developer actually gets access to a virtual super computer and each new Agent contributes to a better build time by contributing its available cores to the build.