Memory Chip Sizes and Dimensions
- The 240-pin unbuffered DIMM chips have 240 pins along the the bottom. The pins plug into the motherboard to secure it in place and allow its use by the processor. Only a 240-pin memory chip can be connected to a 240-pin motherboard interface. Its dimensions are 133.35 mm by 30 mm, with a thickness of 3.18 mm.
- The 240-pin registered DIMM chips are similar in size and interface to 240-pin unbuffered DIMMs. The chips have the same dimensions of the unbuffered DIMMs. Instead of being 3.18 mm thick, the registered chips are 4 mm thick.
- The 200-pin SO-DIMM memory chips interface with the motherboard through a line of 200 pins along the bottom. A 200-pin chip of this kind can be plugged only into a 200-pin slot on the motherboard. Its dimensions are 67.6 mm by 31.75 mm. It has a thickness of 1.9 mm.
