I'm trying to upgrade my GPU from a 1050 ti to a 1660 super.

I've been told my power supply (460 watt) is enough to support this GPU so i went and bought one.

Went to connect it in and the connection that went into the motherboard to power the 1050 doesn't fit into the 1660's supplemented socket (it has a different combination of the 8 square and rounded pins).

Do i still need the power supply plugged into the motherboard when the 1660 has a seperate socket for power on it and what do i need to get to connect power to the new GPU? Please dont say a new power supply.

I tried to make this as understandable as i could, this is my first time diving into the workings of computers.

Thanks in advance