In short yes.
I take it you have at least 2 usb connectors at the front of the case.
And inside you have the two usb blocks from them to connect to the motherboard usb headers.
Because USB headers carry a 5v+ power supply and a 5v-
So connecting anything other than a usb header with cause a short to the motherboard.
Any problem like that would or may cause the motherboard not to power up or post. It is a short circuit.