a8n32-sli deluxe won't boot/post

I recently had a problem with my mobo,at first it would freeze up then it just would not post,it would turn on(heatsink,graphics card,hard drive)but no display,so naturally I started to check everything.I bought another psu still nothing,I bought another graphics card,nothing I tried each of the ram in different slots nothing,so I RMA the board received my new one and it posted for about 5 seconds theen it froze on the asus logo screen and then never posted again(but everything lights up)any suggestions would be appreciated thank you

p.s.I tried to reset the cmos but still got nothing

 

I tried that also,everything lit up but no display

 

the only thing left is the cpu but when I received the new board it posted for about 5 seconds then froze then would not post after that

 

i had a problem like this once but mine was becuase my ram chip had come lose
maybe your ram chip has gone it would explain why there is no screen because during post the graphics uses memory from the ram

 

I tried both I have 2x1Gb sticks of ram on all 4 slots still nothing

 

any other suggestions

 

Have you checked the CPU, is it properly seated, no damaged pins, etc ?

 

yeah I checked that also ,does anybody know how to check a cpu to see if its working(alive)