this is my first build and I am at a loss as to why my board won't start up. It doesn't look like there is anywhere it is being grounded and yes the 24-pin and 8-pin are both connected to the power supply.
When I press the power button the VGA_LED light turns on for a split second then off but nothing else happens. its only the motherboard, no graphics card, ram, cpu or any of that has been put in the motherboard.
If you don't have a case speaker you should look into that. Deciphering the beep codes will help you know where the problem is. See step 16 in the link above, or get one here: http://www.cwc-group.com/casp.html
I have virtually the same board. Mine's the P7P55D EVO.
You can't start the motherboard without the CPU, graphics card, and RAM, at the very least. You can start the motherboard without the hard drives. The CPU initializes the graphics card and the RAM, which is what you would need to see the screen.