Motherboard Or Graphics?

I have a Pc Chips M811 V3.1 motherboard..

The problem is when upon booting the system, i am getting the default beep, however this is a constant beep every 3 seconds or so,even so the monitor will not come on (tried several already working monitors) i have also changed the graphics cards around (also working cards)

Why is the beeping constant? and why is the monitor not going on along with the system?

Many thanks in advance

Kind Regards
John Varney