Hi Smilence,
If you would like to see a clearer picture of what is using up your CPU, download and run Process Explorer
Process Explorer which is quite a bit better than Task Manager and may help you fine tune your options (what and how much can be open at the same time) more easily and also help identify the processes more easily.
Also, there may be many things running in the background that may not be required but taking up valuable resources (maybe not big individually, but a lot collectively). I recommend you download Autoruns
Autoruns for Windows and click on the Everything Tab and see what programs are running at startup and remove/uncheck any that you don't
require - you can always easily add one back later if you find removing one proved to be inconvenient). Do this
only for programs - do
not do it for services (at least for now and not without guidance) - and if you don't know what something is, either find out what it is first or leave it alone until you do know (some changes especially if not to program can cause serious problems - so be SURE before you uncheck anything that you don't know for sure is a program that isn't needed or that you want and, again, uncheck nothing but programs at this point). Remember, many programs that run at startup are NOT required for the program itself to run if you want to use it but there to make it start faster or to automatically check for updates or other reasons that may not be necessary and can reduce the load on the CPU.
If you want, in Process Explorer go to File / Save As and save it as a .txt file and then attach the file to your next post and we'll see if we can identify what is running and what can be done to decrease the impact (if we recognize them ourselves). You can also do the same with Autoruns (make sure you choose a .txt file type) and that may also help us to help you.
I hope this helps.
Good luck!