No display, no post, no beep on a new motherboard!!

Hi all,

I have a similar problem to one that's been answered before on this forum, however scrolling through looking at posts it was rcommended to start my own question for my particular scenario..

So I have recently purchased

gigabyte p67a-ud3p-b3 motherboard
i3 -2130
Patriot DDR3 4 gig 1333 ram
Thermal take 500W psu
And am using a previously owned 512 ASUS graphics card,

I have put computers together before but this time when everything is in place and the power button is pressed it seems like the computer is trying to boot but can't. It is restarting itself sometimes after 1 second, sometimes 3 and other times closer to 10 seconds.
THis is my second motherboard, I have been back to the store today and swapped over the first one I bought, they tested the new motherboard infront of me and it did come up with the "insert system disc" on the screen.

So I took it home only plugged in the basics (VGA, 8 pin motherboard power, 24 pin power, RAM, CPU and power switch) turned it on and it restarted during boot and because i was shocked i was staring at the screen in rage for 3 automatic self restarts then magically it turned on, no beep however same "insert system disc" so I proceeded to plug everything in, testing it once while plugging in HDD's and 2 PCI express cards (same 3 self restarts then insert sys disc).. turned it on again aaafter everything was in and nothing.. same repeat steps but with no display.

Now I have the MB outside my case on cardboard with the basics plugged in and still nothing.. PLLLEEAASSEE HEELLPP

Can u reset the BIOS?
Reset the CMOS memory the right way as is described in the motherboard manual using the clear CMOS link with the power cord unplugged.

How To Clear CMOS @ http://pcsupport.about.com/od/fixt [...] arcmos.htm