MSI 645 Ultra MS-6547 Manual page 65

Glossary
a PC chipset provides the electronic interfaces between all subsystems.
CMOS (complementary metal-oxide semiconductor)
CMOS is a widely used type of semiconductor, which features high speed and low power
consumption. PCs usually contain a small amount of battery-powered CMOS memory to
retain the date, time, and system setup parameters.
COM
In MS-DOS system, the name of a serial communications port. DOS supports four serial
ports. For example, if a modem is connected to one serial port and a serial mouse to another,
they are identified as COM1 and COM2.
DIMM (dual in-line memory module)
A small circuit board that holds memory chips. A SIMM (single in-line memory module) has
a 32-bit path to the memory chips whereas a DIMM has 64-bit path.
DMA (direct memory access)
A transfer mode between the main memory and the peripheral devices that without passing
through the CPU. Using the DMA controller, data is transferred much faster.
DRAM (Dynamic RAM)
A most common type of computer memory. It usually uses one transistor and a capacitor to
represent a bit. As the development of technology, the memory type and specification used in
computer becomes variety, such as SDRAM, DDR SDRAM, and RDRAM. For further
instruction, please see the table below:
Type
FPM (60,70ns)
EDO (50,60,70ns)
SDRAM (66MHz)
SDRAM (100MHz)
SDRAM (133MHz)
RDRAM (Direct Rambus)
DDR SDRAM (100MHz)
DDR SDRAM (133MHz)
* Memory channel width (64 bits started with 75MHz Pentium)
Source: Computer Desktop Encyclopedia
Dynamic RAM (DRAM) Memory Technologies
First Used Clock Rate
1990 25MHz
1994 40MHz
1996 66MHz
1998 100MHz
1999 133MHz
1999 400MHz
2000 100MHz
2000 133MHz
G-2
Peak
Bus* Width
Bandwidth
64 bits 200 MBps
64 bits 320 MBps
64 bits 528 MBps
64 bits 800 MBps
64 bits 1.1 GBps
16 bits 1.6 GBps
64 bits 1.6 GBps
64 bits 2.1 GBps
Volts
5v
5v
3.3v
3.3v
3.3v
2.5v
3.3v
3.3v