Question : Problem: POST audio code question

I have an HP Pavillion m7580n desktop computer that is giving the following POST audio code.

1 long beep followed by about four seconds of silence and then repeats.  

Any clue what this might indicate.  

I get nothing on the monitor.      The video card is not integrated into the motherboard, but a separate card.

Answer : Problem: POST audio code question

Quite possibly, especially if you say it had a hard fall! :-)