There is one more thing that I forgot to ask you.
Please type something again in the search box so that the CPU will get used 100% again, look what time it is and then open Event Viewer and look at all the warnings and errors issued around that time when you typed in the search box. So, let's say it is 9:30 when you type in the search box. Look for all the warnings and errors issued in the Even Viewer between 9:30-9:35. Please let me know what are the warnings and errors, they usually have a code.