Today I was facetiming with someone on my macbook (mid 2010, running 10.6.8., 4 gb ram, c2d) and the cpu usage was crazy and the fans were going into overdrive! i checked activity monitor, over 100%. I just did a clean install for 10.6.3 a week ago because even my scrolling was laggy. Before, when I was on Mountain Lion, it wasn't this laggy. I'm taking it into Apple on Sunday, but I was wondering what possible causes are there?