Push down on the clip, Not bending the port. to remove the cables.

If you are adding a more power hungry card, Use 2x mini 6 pin to etc cables. (what ever you may have on your card) This is to avoid burning the power rails of the motherboard.

On some cards, the cables may need to be removed after sliding the card out due to the clip being not able to be accessed, In that occasion. Hold the card carefully, not yanking the cables.