Understanding Computer Memory - Part 5

Error Correcting Code RAM:

Error Correcting Code works by fixing a single error within 1 bit of 1 byte of data. It does provide, unlike Parity RAM, actual data correction, but only for a single bit of data. If there’s an error involving more than this, most system BIO’s will notify you with a beep code or on screen alert. SIMMS and DIMMS: SIMM means “Single Inline Memory Module.” However, there are single and double sided SIMM’s. Single sided SIMM’s have contacts and chips on only one side while double sided SIMM’s have contacts and chips on both sides of the module. Double sided SIMM’s actually use the same memory bank between both sides (modules on both sides are connected). While it looks like there are separate pins on both sides of these modules, they are actually connected together from both sides equaling one set of pins.

DIMM’s have 2 separate memory banks. Each set of pins on each side of the module are not connected to each other. While SIMM’s typically had a 32 bit data bus, DIMM’s have typically 64 bits or more because they two 32 bit memory banks, one on each side.