Z440 memory upgrade

[MJKnifeworks]

I would like to upgrade my memory either to 32 or 64.The statement below, is it referring to all 8 slots full of the same memory to maximize the performance of the Z440? So 8 X 8gig is better than 4 x16gig. I don't know 64 gig would out perform 32 gig until the 32 ran out and it started paging back and forth to the hard drive.

I see this statement in the quick specs:

To realize full performance at least 1 DIMM must be inserted into each channel.

https://www.dectrader.com/docs/set06/499718/15077_ca.html

[DGroves]

for the z440, Each processor supports up to 4 channels of DDR4 memory.

the z440 motherboard  has 8 dimm slots

memory channels usually have 1,  2 or 4 dimm slots per memory channel

so valid z440 configurations can be

 with one dimm per channel = 4 dimms = max speed

 with 2 dimms per channel 8 dimms also = max speed

some systems will run with unequal dimm channels/amounts of ram

example 3 dimm's used instead of four, (one dimm per channel) will result in single channel, which reduces the max ram xfer rate  

also most systems require each dimm to be the same size and use the same timings for each module

in your example, the max memory speed between the 8/16 gig configurations  is the same

as each one is enabling all four memory channels, however the 16gig example allows dual modules per channel for increased ram capacity