Both DDR memory and SDRAM memory are used in computers and several other devices today. While both types of memory carry out the same task, they do it in slightly different ways. It is important to understand the differences between SDRAM and DDR memory before buying a device that takes either.
Both of these types of memory are not considered dated technology. Although there is DDR2 and DDR3 memory out today, there are still slower devices that utilize the older styles of memory.
The main difference between the two types of memory is how often they transfer information. SDRAM can only transfer 64 bits of data per clock cycle. DDR memory transfers 128 bits of data for every clock cycle and that is because of a key difference between them. There are two positions in every clock cycle, and SDRAM only sends out data at the peak of the cycle, while DDR memory sends data out at both positions. This is what makes DDR memory twice as fast as SDRAM.
SDRAM and DDR memory also have a slight structural difference. On the bottom of SDRAM memory there are 3 strips of contacts while there are only 2 strips on the bottom of DDR memory. While this difference isn’t that significant it is a good way to tell the difference between the type styles of memory if you’re unsure. It is important to keep these differences in mind when looking at any devices that contain these types of memory. Whenever possible opt for the DDR memory over the SDRAM. It doesn’t matter if the memory sizes are identical; the DDR memory is always going to perform better.