Maximum Server Memory adjust in blocks of 1024MB? Our protocol is to set Maximum Server Memory at about 75% of RAM.  For a 4GB RAM, sometimes it gets set at 3000MB and sometimes to 3072MB.  There is a 2 or 3 percent difference in these values.

Is the impact of setting memory at a value that is not evenly dividable by 128, greater then the difference between the rounded and binary values?

Asked differently; 128*23=2944 &amp; 128*24=3072, Does using 3000MB provided a benefit that is between 2944 &amp; 3072 or does it's fractional size disrupt memory usage?
It's reasonable to assume, although I have no way to know, that the difference between allocating 3000 MB and 3072 MB is just those 72 MB as memory allocation is much more granular than, say, 128 or 256 MB.

The minimum amount of memory allocated to each query is 1024 kB, configurable as low as 512 kB (source). A fair guess is that memory allocation units are anywhere between that of disk I/O operations (64 kB = 1 extent = 8 pages) and 512 kB.

Either way, 72 MB back or forth probably won't make any difference.