DDR4 RAM Guide
A practical DDR4 RAM guide covering compatibility, capacity, speed, module formats, matched kits and the key differences from DDR5.
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DDR4★ RAM Guide
Where DDR4 fits
DDR4 is a generation of double-data-rate system memory used by many compatible desktop and laptop★ platforms. It remains relevant when upgrading an existing DDR4 system because adding memory can increase capacity without replacing the whole platform. The key point is compatibility: DDR4 is not a universal drop-in replacement for newer memory standards.
Specifications to check
Before buying, confirm the memory generation, capacity, module type, speed, timings and supported configuration. Desktop DIMMs and laptop SO-DIMMs are different physical formats. The motherboard and processor★ determine what memory is supported, and the system may have limits on total capacity or module population. A matched kit can be preferable where the platform is designed for paired memory operation.
DDR4 versus DDR5★
Kingston states that DDR4 and DDR5 have different electrical specifications, signalling characteristics and physical keying, so they are not interchangeable and cannot be mixed on the same motherboard. Check the exact motherboard documentation rather than assuming that a similar-looking module will fit. When upgrading, compare the cost and benefit of more DDR4 capacity with the alternative of replacing the motherboard★ and platform.