Is DDR5 backwards compatible with DDR4? - Corsair
Can DDR4 fit in DDR5 slot? No, a DDR4 module cannot fit into a DDR5 slot. DDR4 and DDR5 have different physical keying, which means the notches on the modules are placed differently to prevent incorrect installation.
memory - Is DDR4 RAM compatible in a DDR3 RAM slot? - Super User
Originally released in 2014, DDR4 is an older RAM standard than DDR5, released in 2020. ... Can I use DDR4 RAM in a DDR5 slot?
The difference between DDR3 and DDR4 | PC Gamer
The difference between DDR3 and DDR4 RAM, and why DDR4 is usually the right choice.