Have you broken it down to the bare minimum needed to get it to POST?
Ok so I just got a new mobo processor and ram my current set up is
Asrock 970 extreme3
Amd phenom 2 x4 965
Gskill f3-12800cl9d @ 1600mhz
Nvidia gtx460
And an ultra psu I think its 550w I dont remember
Anyway I put it all together today..started it..and can not get any video (cant get to bios..everything is plugged in) ive tried a different cpu and different gpu on both slots and got the same results. Ive put the ram in each slot and cleared cmos each time..no luck.
Please help.

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