I use M3 on different computers. One of them is DELL D610 (very old laptop). I use it as media server - without starting graphics.
It has 1 GB memory installed (DDR2 - 2x512 MB) and setup shown exactly 1GB. "top" and /proc/meminfo shows 1GB too.
But drakconf -> harddrake shows in graphical environment - 2 GB of RAM !. It is something strange for me, maybe anybody knows explanation?