Lakers4us 0 Newbie Poster

i hav been gettin a unmountable boot volume error when i try to start up my pc. it usually appears right after the loading xp screen then either displays a blue screen or restarts by it self. I have tired serverall different things to fix this such as formatting the hardrive and installing a new install of xp, repair the boot files in the recovery console by typing in chkdsk /r or /p , i have done a full format and delete the partiation and reinstall windows xp but for some reason nothing works at all .. please help