check ram

1. Check RAM

cd /tmp
$  wget http://liquidtelecom.dl.sourceforge.net/project/memconf/V3.08/memconf-v3.08.pl.gz
$ gunzip memconf-v3.08.pl.gz
# perl memconf-v3.08.pl -v

whatis-maximum-ram-supported-by-linux-server-computer-system

2. Command
#dmidecode -t 17

Ref: 5-commands-check-memory-usage-linux

3. Check size ram

free -h