DDR3
DIMM: 240 pins
SO-DIMM: 204 pins
Up to 16GB
DDR4
DIMM: 288 pins
SO-DIMM: 260 pins
Up to 65GBs
DDR5
DIMM: 288 pins
SO-DIMM: 262 pins
Up to 256GBs
ECC RAM
Error correction code RAM
Detects and corrects any time a single bit is flipped (on the fly)
Can detect but NOT correct a double bit error