If your laptop is under warranty the first thing that I would suggest is getting in touch with HP. They should be able to give you directions on getting your laptop fixed.
If you are out of warranty I would first suggest checking your ram and hard drive for errors using software such as Memtest
. You may also try replacing the ram if you have any extra laying around or know somebody that does. The worst case scenario would be that you will need a replacement DV6000 Motherboard
If you do not feel comfortable with this I would suggest you search Google maps for a HP authorized repair shop, they should be able to further assist you.