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.