CPU Backplate: This is a metal or plastic plate that sits on the back side of the motherboard, directly behind the CPU socket. Its primary purpose is to provide structural support for the CPU cooler, preventing the motherboard from bending or flexing under the weight and mounting pressure of a heavy heatsink or liquid cooling block.

CPU Contact Frame (or Anti-Bending Bracket): This is a specialized aftermarket accessory that replaces the stock "Integrated Loading Mechanism" (ILM) latch on certain Intel motherboards (like LGA 1700/1851 sockets). It is designed to apply more even pressure across the CPU's integrated heat spreader, which can improve thermal contact and prevent the CPU from bending or warping slightly over time.

CPU Socket Plate (Retention Mechanism): On many modern sockets, there is a metal plate (often part of the socket's locking mechanism) that physically secures the CPU into the socket pins or lands. You flip this plate down and lock it with a lever to ensure good electrical contact between the processor and the motherboard.

Compatibility is Critical: These components are highly specific to the motherboard's socket type (e.g., LGA 1700, AM4, AM5). You cannot use a backplate or mounting bracket designed for one socket type on a motherboard with a different socket.

Installation: If you are building a PC, the cooler you purchase will almost always come with the necessary mounting hardware, including the correct backplate for your specific motherboard socket. You should always follow the cooler manufacturer's specific installation guide.