Performance Issue - Need Assistance

We are facing a major performance issue with Support Center (7013). Basically, whenever our support reps click on a tab, like "Requests" or "Contacts" in particular, it takes an excessive (4-6 secs) amount of time to show. It takes the same amount of time when attempting to view a particular requests.

We have moved the SQL Server DB to a strong server to make sure it was not slowing down the app. After further investigation, it appears that part of the issue is on the client side. When clicking on these tabs or requests, the CPU spikes to ~45% - 60% and stays pinned there for the duration of time. This is occurring on a dual core 3.0GHz CPU. The application server rarely goes over 5% CPU usage as well as the DB server. They are both strong servers.

I really need assistance in resolving this as for we just moved from a solution to this one because of performance/customization issues and now we are getting negative feedback about this solution. Has anyone else experienced this issue? Any assistance is much appreciated.