/ˌdiː diː ˈɑːr fɔːr/
n. — “DDR4: DDR3 that traded fly-by mess for point-to-point purity and pretended 16 banks made it a parallelism god.”
DDR4 (Double Data Rate 4) SDRAM drops to 1.2V with point-to-point signaling (bye-bye fly-by stubs), 16n prefetch, 16-32 banks, and bank group architecture to hit 2133-3200+ MT/s while mocking DDR3's voltage bloat and multi-DIMM crosstalk. Building on DRAM foundations, DDR4 mandates ODT, DBI, CRC, decision feedback equalization, and per-DIMM PMIC power management for eye diagrams that survive 3200MT/s without spontaneous combustion. This workhorse dominated 2010s desktops/servers before DDR5 channelization arrived.
Key characteristics and concepts include:
- 16n prefetch + 16-32 banks faking massive concurrency, with bank groups slashing row conflicts so controllers juggle like caffeinated octopi.
- Point-to-point CK/ADDR/CTL buses to one DIMM per channel, eliminating DDR3 stub carnage while decision feedback cleans marginal eyes.
- PMIC integration delivering clean 1.2V rails, mocking discrete regulation's noise soup at scale.
- DBI+CRC pretending bit errors don't lurk in high-speed data blizzards, plus fine-granularity refresh dodging thermal drama.
In a dual-channel controller dance, DDR4 interleaves rank commands across clean point-to-point links, chasing row hit nirvana while PMIC and ODT conspire to keep signals crisp—delivering workstation bliss until DDR5's two-channel-per-DIMM schtick.
An intuition anchor is to picture DDR4 as DDR3 that got contact lenses and a personal trainer: point-to-point vision eliminates stub-induced blur, bank muscles flex harder, and voltage diet sustains the sprint longer than its wheezing predecessor.