I have this Molex power connector for a fan and they usually have 4 wires. After a quick research I understand there's a yellow and red wire for 5V and 12V, then 2 black wires for grounds. The one I have has only 1 ground and I'm wondering whether that's a problem. It's currently connected to a fan with 4 wires. I can't seem to find an answer to this, so would anyone here be able to help? Greatly appreciated!