sorry if this is a repeat the site froze for several minutes last time I tried to post this. My CPU has refused to run at over 23% for over a day now - all four cores operate at exactly 0.50Ghz out of 2.16 for a minute at a time. I shut off my computer overnight, turned it back on and within 4 minutes it decided to go back to running at 23% consistently(though briefly it was operating at its burst speed of 2.66Ghz). The makes even facebook essentially unmanagable, to say nothing of higher demand websites/applications. It shut off yesterday without saying why when I was operating on battery power - I plugged it back in and the battery was nowhere near drained. The problem started immediately afterwards. Any idea what could be causing this?