What is the difference between GDDR3 and DDR3?

Question

I am trying to buy a laptop, and I have seen in many place that they show GDDR3 and sometimes DDR3. What is the difference between them?

afaik DDR3 is a type of RAM used for system memory, while GDDR3 is a type of RAM used for graphics cards. So does "G" only stand for Graphics or does it have another particular meaning?

Solution 1

GDDR3 vs DDR3

Memory is one crucial component in any computer system. In a standard computer, there are many types of memory employed. The two types of memory that are often confused are DDR3 and GDDR3. DDR3 (Double Data Rate 3) is one type that is used for system memory, which is the main storage for the processor. On the other hand, GDDR3 is another type of memory and the G stands for Graphics. This type of memory is used in graphics cards to store textures and other graphic data.

Graphics cards move a lot of data around and its needs aren’t the same as that of the processor. Because of this, graphics cards need memory that is much faster than what the processor actually needs. GDDR3 fulfills this need but at a much higher cost. While system memories nowadays range from 4GB and higher, graphics memories are still at 1GB or lower.

The main reason why GDDR3 is much faster is its ability to do a read and a write within the same cycle. This lets the graphics card move data around much faster as it would not need to consume 2 cycles to read the memory then replace it. Objects on-screen are represented within memory; when they move, the corresponding entries within the memory are also moved to different memory locations. System memory may not benefit as much with such a capability so it is rather costly to implement the same features within DDR3 for such minimal gain, if any.

DDR3 is a user replaceable part. Even laptops allow access to the memory card slots so that they can be upgraded or replaced. Because of this, DDR3 comes in standardized modules with specific capacities. These modules are notched in a certain manner so that you do not mistakenly force a DDR3 module into a DDR2 slot and vice versa. Because GDDR3 are purchased and utilized by graphics card makers like ATI and NVidia, these do not come in modules but as distinct chips. These are then soldered directly to the board and cannot be replaced.

Summary:

1.DDR3 is a type of RAM used for system memory while GDDR3 is a type of RAM used for graphics cards

2.GDDR3 memory is much faster than DDR3 memory

3.GDDR3 memory is more expensive than DDR3 memory

4.GDDR3 memory addresses can be read and written at once while DDR3 memory addresses cannot

5.GDDR3 comes in chips while DDR3 are in modules

Solution 2

From this

Basically it is a lower power lower heat version of memory based on the DDR2 specification. GDDR3 also features higher bandwidth than traditional DDR2.

so the difference between GDDR3 and DDR3 is that GDDR3 is memory designed for use in graphics cards and is based on DDR2. DDR3 is the successor to DDR2 and is used for computer ram. DDR3 is used with the new intel i7 processors and the AMD Phenom II processors. typically DDR3 has much higher frequencies (around 2000mhz are available now) slightly higher timings of around 7-7-7-20 compared to DDR2's timings of 4-4-4-12. also DDR3 has much higher bandwidth than DDR2 however the increase in actual real world performance is relatively small.

Comments

[Breakthrough]

The actual GDDR3 spec is based off the DDR3 memory specification, but there are indeed changes to make the memory more suitable for a hardware device as opposed to being part of the system memory (e.g. hardware reset capability, increased ability to dissipate heat, as the memory is fixed/soldered and not removable). The Samsung catalog for a surface-mounted GDDR3 module covers a good number of these differences.

[misha256]

This would have been so easy to google. Wikipedia has extensive articles on both DDR and GDDR, and the GDDR article even tells you right away what the "G" stands for!

[Ramhound]

Possible duplicate of How is graphics RAM different from system RAM?