To find out what is the maximum system can support type the following command:
root@websvr:~# dmidecode -t 16
output
# dmidecode 2.11 SMBIOS 2.4 present.
Handle 0x0082, DMI type 16, 15 bytes Physical Memory Array Location: System Board Or Motherboard Use: System Memory Error Correction Type: None Maximum Capacity: 1 TB Error Information Handle: Not Provided Number Of Devices: 64
As you can see the maximum memory capacity is 1 TB