The upgrades, as mentioned earlier, improve efficiency and reduce data access latency. JEDEC also doubled the burst length from eight bytes (BL8) to 16 bytes (BL16). In contrast, DDR5 memory modules come equipped with two independent 32-bit channels (40-bit with ECC). The real game-changer resides at an architectural level that you don't see on the outside of the DIMM.ĭDR4 memory modules sport a single 64-bit channel (72-bit if you take ECC into account). As a result, the position of the notch has changed and will help prevent less-experienced users from trying to insert a DDR5 memory module into a DDR4 slot, or vice versa. Instead, DDR5 retains the arrangement with 288 pins, but the pinouts are different.
Unlike the last transition from DDR3 to DDR4, DDR5 doesn't have more pins than its predecessor. Although JEDEC has specified data rates as low as DDR5-3200, the starting point for many, if not all, mainstream DDR5 products is DDR5-4800. Instead, DDR4-2133 served as the baseline for DDR4.
However, looking back at the beginning of the DDR4 era, DDR4-1600 memory never became a thing.
