My PhpED uses about 30% of CPU all the time. Regardless if it's active or not. It's very annoying because of this the fan becomes very noisy. I don't know of any other program wich causes constantly such high CPU usage. Can I deactivate anything that this will become better?

I have a P4 mobile with 2,2GHz, 512 Ram. I have a lot of files in my project (vBulletin and others).

I agree, this activity is quite high. But it might be caused by background parser that updates the code insight database.
In this case, it will finish sooner or later and will get back to normal 0-1%.
BTW, does it go to 30% immediately after you start it or after some certain steps?

Thanks for the answer. I thought it's always immediatley. But before I have started it just for one little change and the CPU usage is not notable. I even started to debug with no effect. But in the past PHPEd was always the cause of the loud fan. 15 to 30% when not active and even higher wenn active. I will watch that more closely. Usually I have started more programs as now. Maybe some other program is the cause of the high load.

Check the software you recently installed.
You probably know that it's not only phped's DLLs are mapped to the process memory space. Many 3rd party "shared" dlls are injected too. For example ICQ and Logitec. They intercept mouse and keyboard events and do something with them.