How much more does ECC DDR4 cost compared to non-ECC DDR4?

ECC DDR4 costs about $20 to $30 more than the same non-ECC kit — roughly 30% extra for a 32GB kit at the same speed and latency. For example, a 32GB (2x16GB) DDR4-3200 CL22 non-ECC kit might cost $55-65, while the ECC version is around $75-85. The premium is small because ECC DDR4 is standard for servers and produced in volume, while consumer non-ECC is often cheaper due to lower cost and higher competition.