cct(clock cycle time，时钟周期)
db: deep buffer(深度缓冲)
ddr sdram(double date rate，双数据率sdram)
dil(dual-in-line)
dimm(dual in-line memory modules，双重内嵌式内存模块)
dram(dynamic random access memory，动态随机存储器)
drdram(direct rambus dram，直接rambus内存)
ecc(error checking and correction，错误检查修正)
eeprom(electrically erasable programmable rom，电擦写可编程只读存储器)
fm: flash memory(快闪存储器)
