COMPTIA A+ Practice Exam

How many pins does DDR memory have?

1. 168 pins

2. 200 pins

3. 184 pins

4. 240 pins

The correct answer is: 184 pins

DDR (Double Data Rate) memory is designed to transfer data on both the rising and falling edges of the clock cycle, which allows for increased data throughput compared to its predecessor, SDRAM (Single Data Rate Synchronous Dynamic Random-Access Memory). The specific pin count refers to the physical design of the memory module. DDR SDRAM, specifically as it relates to the DIMM (Dual Inline Memory Module) format, typically has 184 pins. This distinguishes it from other types of RAM. For instance, DDR2 memory also has 240 pins, which is another type of DDR memory, but it is backward incompatible with DDR due to the difference in pin layout and signaling. The choice of 184 pins is significant because it defines the physical structure of the DDR memory module. When selecting memory for a motherboard, matching the pin count is critical, as mismatched pin configurations will prevent the memory from being installed properly. Understanding these details about DDR memory is critical for anyone working with computer hardware or studying for the CompTIA A+ certification.