I got a problem , at 250/1000 freqs when I play a video sometimes it gets stuck and I have to close the media player , so I thought the voltage on 500 mhz freq it's too low and I made limits 250/500 to test these two freqs . While playing several videos I had putty open in background and waiting the video to crash , when it crashed I used "awk '{print $1/1000" MHz"}' /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq" command and I got 550Mhz and it got stuck at this frequency till I open again mediaplayer . What actually makes the frequency jump over the limit ? :-/