DDR RAM – DDR2 RAM – DDR3 RAM Difference
October 9th, 2009Are you looking to find the difference between DDR RAM, DDR2 RAM and DDR3 RAM Memory Modules For Laptops(SODIMM). Here in this picture we provided the dimension and number of pins on each Memory Module. By looking into this picture, you may confuse a bit as there is no physical difference between DDR and DDR2 SODIMMs. There are so many guides available to identify the differences between DDR and DDR2 RAMs. Most of them discussed about DIMM Memory Modules which is very easy to distiguish as the DDR DIMM is 184Pin whereas the DDR2 DIMM is 240 pin. Also the notches will be on different position. But what about SODIMM Modules which say 200 pin on DDR and DDR2. We explained the differences here and it is very easy to distinguish.
Fist of all have a good look at the below image. It tells you a rough dimension and number of pins on each memory modules.
DDRRAM-DDR2RAM-DDR3RAM-Laptop RAM
Actually it is very easy to find the difference on DDR3 RAM from DDR & DDR2 RAM Modules. The dimension and Number of pins are entirely different. So, we are going to look the main differences between DDR and DDR2 Laptop Memory Modules (SODIMM).
DDR RAM – SODIMM – Some technical details
DDR RAMs are built on TSOP(Thin Samll Outline Package) TypeII packages. The ICs on the PCB(Printed circuit board) are of 66pins. The ICs are 10.16mm Width and 22.22mm Length. Also on the back side, you can see the leads protrude beyound the soldering. And the most important factor is, the PCBs are of 1mm thick.
DDR2 RAM -SODIMM- Some technical details
DDR2 RAMs are built on FBGA(Fine Ball Grid Araay) based on BGA(Ball Grid Array) Technology. The thickness of the PCB here will be 4mm(approx). Also you can not see any leads protruded on the back side of the PCB. You can feel only the ball heads of melted soldering balls.
Care before inserting DDR and DDR2 SODIMM RAM on the slot
As both the DDR and DDR2 SODIMM Modules are looks same, there are slight chances anyone may try to interchange the types. Actually it is not possible to interchange. Look at the image below to see the slot offset difference.
DDR RAM - DDR2 RAM Slot Difference
For Our Readers:
You may find some mistakes on the above explanation or you may have some words to say about this guide.
We request you to leave a comment below.
A Good software to find all about you DDR RAM is CPU-Z.
The CPU-Z software program is the free and you can get it from many places. Do a Google search for the term ” CPU-Z Download ” and you will get this program to save and install on your computer. Once installed as per instruction following the installation wizard, re-start the computer and run the program. This program once started will give all the above mentioned details on the “CPU” and “Memory” panels by switching the panels from the top lined tabs. Once you got all the details, you may contact your memory module vendor or the manufacturer’s technical representative to get the confirmation of the RAM memory module to use on your system. If you are going to buy a DDR RAM from a online shopping website, make sure there is a return policy if the memory module is not well suit with your computer.
Here the Effective Memory clock speed is the very common frequency written on the packing and on the memory module itself. The actual memory clock is different on DDR1, DDR2 and DDR3.
Effective Memory Clock For:
DDR1 RAM – 2xMemory Clock
DDR2 RAM – 4xMemory Clock
DDR3 RAM – 8xMemory Clock
An Example for memory clock speed of 100MHz on all three DDR RAM types. Let us calculate the effective memory clock speed for all the three types.
Effective Memory clock for DDR1/100MHz/DDR-200/PC-1600 = 2×100 = 200MHz
Effective Memory clock for DDR2/100MHz/DDR2-400/PC2-3200= 4×100 = 400MHz
Effective Memory clock for DDR3/100MHz/DDR3-800/PC3-6400 = 8×100 = 800MHz
Now using the above example, it is very easy to identify what kind of DDR RAM is on a Computer or Laptop.