High CPU usage when open a IVF solution with MSVS 2010

I am using MSVS 2010 + Cluster Studio 13 (updated last week). When I open my solution (some c projects and some fortran projects), the CPU usage went up and never came down. The trouble maker could be the parser.

I have a project contains 200+ .f90 files and 100+ _inc.f90 (header) files. The parser went smothly when the project first load. It said that "Parse file xxxxx.f90". But later it slowed down with increase of CPU usage.

Then in the end the CPU usage stayed around 13% without doing anything. (see attachment)

My computer has windows 7 64bit installed. i7 + 8G ram. 

Does anyone have a similar problem? Is there a way to fix it?