ive had this problem before. bad hard drive. it could be a number of things. over heat. Is ur comp in an enclosed area with little ventilation? Ive built a little exhaust pipe for mine, dropped the temp when playing bf2 by about 7 - 10 degrees C.
Dosent pre-built computers have a special partition on their hard drive that holds all the drivers? If its a newer comp it should, if its really old I dont know then. HP site should have all drivers.
I coulda donated a mil but i lost my 10 mil when i got frozen. Ill be back up to a mill hopefully by the end of the week. that sounds like fun though good luck.