See if the screw holes on the board line up with the holes on your computer case, if they do not, then your case and motherboard are not compatible. Next, you will need to install a set of stand offs, these screw into the case and then have holes for the actual motherboard screws on top of them that your motherboard screws will go into. This keeps the motherboard from making contact with the side of your case, as this can damage your motherboard, especially if your motherboard has an electrical current running through it (as in it is powered on).
if your computer case did not come with any, you can buy them at sites such as Tiger Direct, New Egg, etc.
Next, after you screw in these standoffs, then just screw in your motherboard and that is it, make sure you have secured but not over-tightened the screws and that the motherboard is not directly coming in contact with any part of your case.
Perhaps, because there might be not enough place after you install the motherboard to install your drives. The CPU or the RAMs might be in they way. There is surely no other magical reason to it.
Before mounting the motherboard in the case I like to install the CPU and CPU fan/heatsink on to the motherboard. In fact, it is recommended to install the CPU & heatsink while the motherboard is still our of the case to make the job easier.
Install the motherboard first. The drives will have wiring harness to connect to the motherboard.
The motherboard
Bad PSU, (power supply). Did not install motherboard right in case, and bad ground.
systems unit
The Motherboard..
It should tell you in more detail with the instruction but first you slide open your computers case, then you insert the card into the matching slot on your computer's motherboard, then you close your computer back up and install the software.
Making sure that the computer case you have is appropriate for the motherboard is the first step. Then it is much like legos. The motherboard will only fit in the computer case in one way. So will the Processor, the harddrive, the ram, the processor fan, and all the other parts. Do not force anything into place, if it does not go in easily try reorienting it. (The motherboard usually has screws and mounts, line them up with the case, and do not fret)
The computer case.
nlx
Because you might drop the drives on your motherboard while installing.