i bought my pc 6 months ago..and up to now, i cant use it continously!! heres my brief story, i have a brand new pc,new installed OS then after how many days, it hanged,,then i went to the shop where i bought it, then told me that it is the cause of OS, then i tried new OS(XP SP2), it works for how many weeks then my windows media player is corrupted (there is a message "dont send" in option)..then i tried to upgrade it and a new version of media player was installed, but still the same..then i told this to my friend and told me my OS might be the problem, then what i did, i reformat again and installed new OS, then after 2 days, system failure happens, then i reformat again, put new OS, i used the OS of my friend which he is using where he never encountered a problem using it, then when i used it after 2 days again, FREEZE! i dont know what is the problem, the shop keeps telling me its because of OS, my OS is not original,but i used the OS of my friend which is working for him for a very long time, how could this be an OS? and one more thing, i hear a "tuk" sound in my CPU sometimes,is that normal?can someone give me idea what is the problem?could it be the HD 500gb be the culprit???