### DDR3 and DDR4 RAM???

Once I was wondering what is the difference between DDR3 RAM and DDR3L RAM. Since there is a newer DDR4 RAM available nowadays, why there's another DDR3 RAM? Later I found out that it was designed to overcome performance issues with motherboards and processors.

I was wondering why all the leading memory manufacturing companies came up with a DDR3L. Basically DDR3 and DDR4 RAM notches are not identical. So you can't fit both RAMs in the same motherboard. But hey what if the current RAM you have is not enough or not fast enough? With current motherboard and processor limitations, the maximum speed a DDR3 RAM can work is 1600 MHz. But a DDR4 RAM can work at a speed starting from 2133 MHz.

Apart from the speed, DDR4 RAM operates at a lower voltage as 1.2V thus it consumes lesser energy than the DDR3. This might not show any significance in a Desktop or a Laptop computer but in a server farm where they are using hundreds of RAMs, this is saving a lot of energy.

### Why a DDR3L???

The current computer market has given up DDR2 and DDR1 RAMs already. It will be nearly impossible to find any hardware that support those RAMs. The newer processors and motherboards have already started to make their way away from DDR3 RAMs. But there will be a consumer market to DDR3 family for another few years. To support this community, memory manufacturing companies have come up with a new version which supersedes the DDR3 RAM; DDR3L...

• DDR3 RAM operates at 1.5V when DDR3L RAM operates at 1.35V
• DDR3L RAM is a little bit expensive than the DDR3 RAM

In an electronics perspective, this voltage difference can be expressed as a factor which increase the speed of the DDR3L. Computers work in binary. Normally in a DDR3 RAM, 0V is considered a 0 bit and 1.5V is considered as a 1 bit. The circuitry inside those black chips takes time to switch between these two voltage levels. We call it the transition time.

Transition time is calculated by measuring the time taken for the circuit to reach the voltage level corresponding to bit 1 from bit 0. It's quiet clear that it will take a longer time to reach 1.5V than 1.35V. Hence DDR3L RAM will be much faster than DDR3 RAM. So, using the same physical layout (notches...) one can use a DDR3L RAM with the same motherboard without replacing it.

### Facts to consider when replacing a DDR3 RAM with a DDR3L

Intel 4th generation processors are supporting both the DDR3 and DDR3L RAMs. So if you're using one of those processors, you can replace. Also check motherboard compatibility with the DDR3L RAM. Even though the slot is the same, some motherboards (old ones mostly)do not support DDR3L.