Memory Conversion

[Anomaly1964]

Is there some formula for knowing that DDR4-2666 is PC4-21300 or is it just something you memorize?

 

[IntelUser2000]

Yes there's a formula.

System memory in Desktops and Laptops are 64-bits wide. 2666 in DDR4-2666 refers to the transfer speed in MegaTransfers/s(MT/s).

2666 MT/s x 64 bits x 8 bits/byte = 21,328MB/s or 21.3GB/s. That's how you get PC4-21300.

 

[deustroop]

https://en.wikipedia.org/wiki/Double_data_rate

 

[Anomaly1964]

Yes there's a formula.

System memory in Desktops and Laptops are 64-bits wide. 2666 in DDR4-2666 refers to the transfer speed in MegaTransfers/s(MT/s).

2666 MT/s x 64 bits x 8 bits/byte = 21,328MB/s or 21.3GB/s. That's how you get PC4-21300.

Shouldn't it be (2666x64)/8... ?

 

[IntelUser2000]

Shouldn't it be (2666x64)/8... ?

You can make it simpler and do 2666 x 8 since you know 64 bits equal 8 bytes.

I guess it has to be,
2666 MT/s x 64 bits x byte/8 bits

But you get the idea how they got those numbers. It's not something that was randomly assigned.