DDR4 bandwidth calculation = DDR4 memory clock frequency x 2 x total DQ width
For instance, using your example
DDR4 BW = 300MHz x 2 x 144 = 86.4MT/s
I am not sure how does the 2.4GT/s calculation comes from
I had found the below details in the Wikipedia Page https://en.wikipedia.org/wiki/Double_data_rate
Memory Clock - 300MHz
I/O Bus Clock - 1200MHz
Transfer rate - 2.4GT/s
Theoretical Bandwidth - 19.2GB/s
How were these numbers derived?
2.4GT/s Transfer rate =1200MHz x 2
19.2GB/s Theoretical Bandwidth = (1200MHz x 2 x 64 bit DQ) = 153.6Gb/s = 19.2GB/s
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