The easiest way to check your RPC activity is with Perf Mon. Open a perf mon session for that machine and monitor your individual processes and check which one is using the most resource. Once you've isolated your thread using the most resources, check how many Virtual Bytes the process is trying to use. This would usually be an app trying to do a remote operation. Should the virtual bytes be large, it indicates that that's the amount of resources it's trying to use (Virtual Bytes that is). You have to execute perf mon on the machine as RPC will not allow another connection if it claims to be too busy!