So I'm trying to install a new motherboard I bought into this case but something perplexes me. I put the standoffs in but there is this peg coming out from the case where I would want to put a screw in for the motherboard. It looks like a standoff but will not come off and it's solid with no screw lines. The case is a HEC 6C60BS Black / Silver Steel ATX Mid Tower. Can anyone tell me what this is and what it is for?