citation needed Variants Variants of DIMMs support DDR, DDR2, DDR3, DDR4 and DDR5 RAM. The following figure also shows a 2+2 & 4+4 configuration in dual channel, illustrating that the paired slots will continue to run in dual channel mode as long as the capacities across channels match (thus it's 6 GiB per channel in dual-channel configuration). Many enhancements have occurred to the modules in the intervening years, but the word 'DIMM' has remained as a generic term for computer memory modules. That 2 GiB + 2 GiB = 4 GiB is a coincidence. In other words, the 4 GiB size of the other module is just for illustration that the sizes need not match in that case. In the example, that means 4 GiB dual channel RAM from the 2+2 configuration plus 4 GiB of single channel RAM from the single 4 GiB RAM module. (DIMM1 and DIMM2, as well as DIMM3 and DIMM4, seem to be paired, so you cannot install matching size modules into DIMM1 and DIMM4, for instance, despite them technically being on different channels as well.) Extra, unpaired RAM modules will run in single-channel mode, no matter their capacity. Its maximum data storage capacity is 32-bit/cycle, and its voltage capacity is 5V. In order to make use of dual-channel operation, both channels should have a RAM module with matching capacity, hence the manual suggests installing two matching-capacity modules into DIMM1 and DIMM2. The discussed modules are further divided into two types: Single in-line memory module (SIMM): Under the SIMM configuration, pins are present on one side of the module and are shorted together. In the figure, DIMM1 and DIMM3 are on channel A, whereas DIMM2 and DIMM4 are on channel B. According to the service guide, there are at minimum 4 slots that do have to be filled before all others. DIMM slots of the same colour indicate different channels.

Dimm slots are further divided into