One last easy check - grounding issues. And it's easy with the board out. Check inside the case, you should find 9 copper stand-offs (if the board is ATX), which you used to secure the board with 9 screws.
Now, how many stand-offs are installed, and do they line up with the 9 holes on the board? If there are too many, or a single one is mislocated, then a short can happen which will prevent the board from booting properly.
__________________ Somewhere, an electric company is salivating... |