The java virtual maschine (jvm) always requires a value for the maximum of available memory for this jvm instance.
This limit could be changed by editing the properties of the windows link (Aristoteles3D without .exe). Within the property dialogs target field is an option -J-XmxYYYm. replace the YYY by your memory limit, e.g. 700 MB -> -J-Xmx700m and restart the viewer by executing (double click) the link.
This limit could be changed by editing the start.bat file. Within the file is an option -J-XmxYYYm. replace the YYY by your memory limit, e.g. 700 MB -> -J-Xmx700m and restart the viewer by executing the start.bat.