Search results
Results from the WOW.Com Content Network
In computing, a memory module or RAM stick is a printed circuit board on which memory integrated circuits are mounted. [ 1 ] Memory modules permit easy installation and replacement in electronic systems, especially computers such as personal computers , workstations , and servers .
DDR2 is a 240-pin module, DDR is a 184-pin module. Notebooks have 200-pin SO-DIMMs for DDR and DDR2; however, the notch on DDR2 modules is in a slightly different position than on DDR modules. Higher-speed DDR2 DIMMs can be mixed with lower-speed DDR2 DIMMs, although the memory controller will operate all DIMMs at same speed as the lowest-speed ...
There is a common belief that number of module ranks equals number of sides. As above data shows, this is not true. One can also find 2-side/1-rank modules. One can even think of a 1-side/2-rank memory module having 16(18) chips on single side ×8 each, but it is unlikely such a module was ever produced.
A DIMM (Dual In-Line Memory Module) is a popular type of memory module used in computers. It is a printed circuit board with one or both sides (front and back) holding DRAM chips and pins . [ 1 ] The vast majority of DIMMs are manufactured in compliance with JEDEC memory standards , although there are proprietary DIMMs.
With two transfers per cycle of a quadrupled clock signal, a 64-bit wide DDR3 module may achieve a transfer rate of up to 64 times the memory clock speed. With data being transferred 64 bits at a time per memory module, DDR3 SDRAM gives a transfer rate of (memory clock rate) × 4 (for bus clock multiplier) × 2 (for data rate) × 64 (number of ...
RDRAM was also up to four times more expensive than PC-133 SDRAM due to a combination of higher manufacturing costs and high license fees. [ citation needed ] PC-2100 DDR SDRAM , introduced in 2000, operated with a clock rate of 133 MHz and delivered 2100 MB/s over a 64-bit bus using a 184-pin DIMM form factor.
The number of chip ID bits remains at three bits, allowing up to eight stacked chips (3 → 3). A third bank group bit (BG2) was added, allowing up to eight bank groups (2 → 3). The maximum number of banks per bank group remains at four (2 → 2), The number of row address bits remains at 17, for a maximum of 128K rows (17 → 17).
Some measurements of modules are size, width, speed, and latency. A memory module consists of a multiple of the memory chips to equal the desired module width. So a 32-bit SIMM module could be composed of four 8-bit wide (×8) chips. As noted in the memory channel part, one physical module can be made up of one or more logical ranks.