which is better and why?

Solution
depends, on the frequency and bus width of the memory. as far as im aware, ddr5 is generally faster, as it more often comes in faster speeds, but technically you could run ddr5 and ddr3 at the same MHZ, data bus width (bits) and timings and they would perform identically, the ddr5 however would use less power.
depends, on the frequency and bus width of the memory. as far as im aware, ddr5 is generally faster, as it more often comes in faster speeds, but technically you could run ddr5 and ddr3 at the same MHZ, data bus width (bits) and timings and they would perform identically, the ddr5 however would use less power.
 
Solution