Thanks, I did a quick work, everything is on the correct position; I also clean the CPU and CPU area. I noticed also that heatsink is also very hot. I just want to add that even my computer is power off during 1 week, as soon as I switch it on the temperature started immediately with 55c or 60c, then next during 1 hour or less or when I click or do lots windows the computer reboot alone, anyway I will buy a new fan with a heatsink and do everything you told me as a first step.
also the weater here in my country is so cold at this point of time.
Sorry if my English is bad