So i finished building my pc a few weeks ago and today i noticed one of the power cords going to the GPU looks loose. It has a 6 and a 6+2 cable going into it and the 2 cable is almost falling out. I have since fully plugged it in. However, I was wondering what would happen if this fully came out? would it be entirely unable to work without it being connected or would it just run slow?
Depending on the card. Some won't run if the +2 connector (redundant grounds) is missing, some don't care. I have an old card that doesn't care, and newer cards that do care.
But I would contact the PSU manufacturer and explain the issue. If the PSU is modular, they should send you a new cable.