1) Remove EVERYTHING from the case
2) Set the motherboard on a non conductive surface. The motherboard box is perfect for this. .DO NOT PLACE THE MOTHERBOARD ON THE STATIC BAG! The outside of some of these can actually conduct electricity! We are going to try and assemble a running system outside of the case.
3) Install the CPU and heat sink.
4) Install the RAM (only install 1 stick for SDRAM, 2 for RDRAM)
5) Install the video card. Do make sure the card is FULLY seated.
6) Connect the monitor to the video card.
7) Connect the power supply to the motherboard. Do make sure you plug in the extra power connector [if used]
8) Connect power to the power supply
9) Do NOT connect ANYTHING else. Make sure you have the power connector on the CPU fan connected.
10) Use a small screwdriver to momentarily short the power switch connector on the motherboard.
If all is well, it should power up and you should get a display. You now have found you have a mounting problem. The board is shorting to the case. If not, then you most likely have a faulty component. You will need to swap parts with known good units ie power supply, cpu, ram, video card.