Random access memory
SIMM
For more information on 72-Pin SIMM's click
here.
SDRAM
SDRAM memory modules have 168 pins and two
notches [Wikipedia]
DDR memory modules have 184 pins and one notch [Wikipedia]
- 100 MHz = DDR200 = PC1600 (64 bit * 2 * 100 MHz = 1600 MB/s)
- 133 MHz = DDR266 = PC2100 (64 bit * 2 * 133 MHz = 2133 MB/s)
- 166 MHz = DDR333 = PC2700 (64 bit * 2 * 166 MHz = 2666 MB/s)
- 200 MHz = DDR400 = PC3200 (64 bit * 2 * 200 MHz = 3200 MB/s)
SDRAM modules have 240 pins and one notch. The notch on DDR2 DIMMs is in a different position than DDR DIMMs, and the pin density is slightly higher. [Wikipedia]
- 200 MHz = DDR2-400 = PC2-3200 (64 bit * 2 * 200 MHz = 3200 MB/s)
- 266 MHz = DDR2-533 = PC2-4200 (64 bit * 2 * 266 MHz = 4256 MB/s)
- 333 MHz = DDR2-667 = PC2-5300 (64 bit * 2 * 333 MHz = 5328 MB/s)
- 400 MHz = DDR2-800 = PC2-6400 (64 bit * 2 * 400 MHz = 6400 MB/s)
SO-DIMMs have 72, 100, 144 200 or 204 pins and one or two notches [Wikipedia]
- 100-pin SO-DIMMs have two notches
- 144-pin SO-DIMMs have a single notch near (but not at) the center
- 200-pin SO-DIMMs have a single notch nearer to one side (20/80)
- For DDR1 the notch is slighly more outboard i.e the offset/blank space for the notch is inboard
- For DDR2 the notch is slighly more inboard i.e the offset/blank space for the notch is outboard
- 204-pin SO-DIMMs have a single notch nearer to the center than 200-pin SO-DIMMs (36/66) for DDR3