Is DDR5 backwards compatible with DDR4?

The ASUS motherboard lineup will include models with DDR5 support for the high-end, while for the low-end it will still use DDR4 The type of memory supported

Is DDR5 backwards compatible with DDR4? check your manual but generally with two sticks A2B2 is what you should be using Exactly this, what if you bought a mobo with only 2 slots?

The ASUS motherboard lineup will include models with DDR5 support for the high-end, while for the low-end it will still use DDR4 The type of memory supported

can i use m2 sata in nvme slot DDR4 memory modules sport a single 64-bit channel In contrast, DDR5 memory modules come equipped with two

No, you can not

can you own a slot machine Instead, the only practical use case we can think of is to repurpose your existing DDR4 memory until DDR5 becomes a more attractive proposition,

No The sticks are physically different DDR4 wont fit in a DDR5 slot and vice versa