[HELP] High CPU!

My server uses very much CPU, I am not sure whether this is a problem or not.
When nobody is logged on, it uses 00 CPU (not surprising at all) but when 1 person logs on, the CPU of the GameServer will reach 30, and CPU of the LoginServer will reach 40. It is not a constant number, but on average, the LoginServer uses 10 more CPU than the GameServer.
Anyone knows what could cause it, or preferably, could somebody help me out, over team viewer?

Thread.Sleep at the end of the looping routine.

I can't believe that I actually forgot to do this.
Thanks a lot, it works now.
However, there's one problem, the client doesn't get further as "Initializing...", so that's the next problem, it worked before, so it should be something small, maybe you know what, I'll keep this updated.

Fixed. I over-used it, used it at the wrong places, etc.
I request a moderator to close this thread.