My hp laptop wont turn on

Hello,
hi i am using my HP dv2000 laptop from 3 years i dont have any problem but now it started giving me trouble, when i turned on i heard 2 beeps and havent turned on. i tried all the folling steps still its not working
*Take out the battery,
*Remove main supply,
*Hold power button down for 30 secs,
*Put only power supply in, do not put battery in
*Turn laptop on
*Put the battery in.
please please can any one tell me the solution for this.