What is the difference between DDR2 and DDR3 ram?
On the appearance, both DDR3 and DDR2 use 240 pins and you can hardly see any differences between them. The only difference is the position of the key notch that prevents users from inserting the wrong type of RAM into their motherboards. The shift in the position of the key notch also means that DDR3 is not compatible with DDR2 and a separate DIMM slot has to be used. Other than the difference in key notch position, DDR3 RAM is also due to run at a higher frequency than DDR2 RAM. When JEDEC set the standard for DDR2 RAM, it never intends to make it run beyond 800MHz. The official specification states that DDR speeds ran to DDR-400, DDR2 from 400 to 800, and DDR3 800 to 1600. Due to the fact that DDR2 800 and 1066 (an overclock version of DDR2 800) exist, DDR3 800 and 1066 will become an overlap speed with that of DDR2. As such, it will only be 1333 that is the first DDR3 speed to have better frequency/speed performance over the DDR2 RAM. While the difference between DDR and DDR2 RAM l
