Computer powers on then continously beeps

Hello,

I've got a PB ixtreme 9600, its been working fine since i got it, till today. The screen froze in the middle of playing a game, so i assumed it was a graphic's error and powered down the pc. Now when i power up the pc it starts to beep (continous beep tha lasts around 15 seconds then pauses for 1 or 2 seconds then beeps for a further 15, and so on) the screen says that it has no signal, thou i can hear the HD and the DVD drives spinning, and the pc does not boot. I have read the forum and have tried various ways to try to diagnose the problem, mainly suggested by DJAkshay.

I have removed the ram, and graphics card. Swapped the ram around into other slots. Tried the eraser technique on the ram and the graphics card. Disconnected everything from the motherboard till only the cpu and its cooling fan were left in. I have also done the cpu check of powering the computer on for a few seconds and checking that it gets warm, which it does. It doesnt matter what i do the beeping continues and the pc does not boot. Does this mean my motherboard is dead? Any suggestions on how to deal with the problem is welcome.