What is the pin configuration of a DDR2 DIMMs?

DDR2 DIMMs have a total of 240 pins. The pin configuration includes a notch on the bottom edge to ensure proper alignment when inserted into a motherboard. Pins are arranged in two rows, with specific pins designated for power, ground, data, and control signals. DDR2 also features a different keying mechanism compared to its predecessor, DDR, to prevent incompatible installations.