Why my cpu got dood dood sound?

[charlizelip]

My CPU started to have dood...dood sound since this week. I heard it during the startup after everything is loaded. Today it has changed to 4 doods sound from 2 doods only. The dood sound is like the sound which i enter into safe mode, i don't know what is the problem but i feel that it is a hard disk problem. I am using Windows XP Pro, Western Digital hard disk, P 4 HT 2.4Ghz, 512 ram, 1 1/2 year old.

 

[OS Dragon]

I think it is a passing occurance, because I think this has happened on my..laptop aswell. I rarely get it - very rarely.