PC100 is a standard for internal removable computer random access memory, defined by the JEDEC. PC100 refers to Synchronous DRAM

SDRAM

Synchronous dynamic random access memory is dynamic random access memory that is synchronized with the system bus. Classic DRAM has an asynchronous interface, which means that it responds as quickly as possible to changes in control inputs...

 operating at a clock frequency of 100 MHz, on a 64-bit-wide bus, at a voltage of 3.3 V. PC100 is available in 168-pin DIMM

DIMM

A DIMM or dual in-line memory module, comprises a series of dynamic random-access memory integrated circuits. These modules are mounted on a printed circuit board and designed for use in personal computers, workstations and servers...

 and 144-pin SO-DIMM

SO-DIMM

A SO-DIMM, or small outline dual in-line memory module, is a type of computer memory built using integrated circuits.SO-DIMMs are a smaller alternative to a DIMM, being roughly half the size of regular DIMMs...

 form factor

Form factor

Form factor may refer to:*Form factor or emissivity, the proportion of energy transmitted by that object which can be transferred to another object...

s. PC100 is backward compatible with PC66

PC66

PC66 refers to internal removable computer memory standard defined by the JEDEC. PC66 is Synchronous DRAM operating at a clock frequency of 66.66 MHz, on a 64-bit bus, at a voltage of 3.3 V. PC66 is available in 168 pin DIMM and 144 pin SO-DIMM form factors. The theoretical bandwidth is...

 and was superseded by the PC133

PC133

PC133 is a computer memory standard defined by the JEDEC. PC133 refers to Synchronous DRAM operating at a clock frequency of 133 MHz, on a 64-bit-wide bus, at a voltage of 3.3 V. PC133 is available in 168 pin DIMM and 144 pin SO-DIMM form factors...

 standard.

A module built out of 100 MHz SDRAM chips is not necessarily capable of operating at 100 MHz. The PC100 standard specifies the capabilities of the memory module as a whole.
PC100 is used in many older computers; PCs around the early 2000s were the most common computers with PC100 memory.

See also

• PC66
  PC66
  PC66 refers to internal removable computer memory standard defined by the JEDEC. PC66 is Synchronous DRAM operating at a clock frequency of 66.66 MHz, on a 64-bit bus, at a voltage of 3.3 V. PC66 is available in 168 pin DIMM and 144 pin SO-DIMM form factors. The theoretical bandwidth is...
  
  
• PC133
  PC133
  PC133 is a computer memory standard defined by the JEDEC. PC133 refers to Synchronous DRAM operating at a clock frequency of 133 MHz, on a 64-bit-wide bus, at a voltage of 3.3 V. PC133 is available in 168 pin DIMM and 144 pin SO-DIMM form factors...
  
  
• PC1600
• PC2100
• PC2700
• PC3200

• DRAM
  Dram
  Dram or DRAM may refer to:As a unit of measure:* Dram , an imperial unit of mass and volume* Armenian dram, a monetary unit* Dirham, a unit of currency in several Arab nationsOther uses:...
  
  
• SDRAM
  SDRAM
  Synchronous dynamic random access memory is dynamic random access memory that is synchronized with the system bus. Classic DRAM has an asynchronous interface, which means that it responds as quickly as possible to changes in control inputs...
  
  
• DDR SDRAM
  DDR SDRAM
  Double data rate synchronous dynamic random access memory is a class of memory integrated circuits used in computers. DDR SDRAM has been superseded by DDR2 SDRAM and DDR3 SDRAM, neither of which are either forward or backward compatible with DDR SDRAM, meaning that DDR2 or DDR3 memory modules...
  
  
• DIMM
  DIMM
  A DIMM or dual in-line memory module, comprises a series of dynamic random-access memory integrated circuits. These modules are mounted on a printed circuit board and designed for use in personal computers, workstations and servers...
  
  
• SO-DIMM
  SO-DIMM
  A SO-DIMM, or small outline dual in-line memory module, is a type of computer memory built using integrated circuits.SO-DIMMs are a smaller alternative to a DIMM, being roughly half the size of regular DIMMs...