sdram, pc, ddr etc.
- Thread starter jp198780
- Start date
...
Dual Data Rate, PC means MB/s
The first number, xxx, indicates the maximum clock speed that the memory chips support. For instance, DDR400 memories work at 400 MHz at the most, and DDR2-667 can work up to 667 MHz. It is important to notice that this is not the real clock speed of the memory: the real clock of the DDR and DDR2 memories is half the labeled clock speed. This way, in fact, DDR400 memories work at 200 MHz and DDR2-667 memories work at 333 MHz.
The second number indicates the maximum transfer rate that the memory reaches, in MB/s. DDR400 memories transfer data at 3,200 MB/s at the most, hence they are labeled as PC3200. DDR2-667 memories transfer data at 5,336 MB/s and they are labeled as PC2-5400. As you can see, we use the number “2” after “DDR” or “PC” to indicate that we are talking about DDR2 memory, not DDR.
The first number, xxx, indicates the maximum clock speed that the memory chips support. For instance, DDR400 memories work at 400 MHz at the most, and DDR2-667 can work up to 667 MHz. It is important to notice that this is not the real clock speed of the memory: the real clock of the DDR and DDR2 memories is half the labeled clock speed. This way, in fact, DDR400 memories work at 200 MHz and DDR2-667 memories work at 333 MHz.
The second number indicates the maximum transfer rate that the memory reaches, in MB/s. DDR400 memories transfer data at 3,200 MB/s at the most, hence they are labeled as PC3200. DDR2-667 memories transfer data at 5,336 MB/s and they are labeled as PC2-5400. As you can see, we use the number “2” after “DDR” or “PC” to indicate that we are talking about DDR2 memory, not DDR.
Last edited: