ubuntu: 8Gb machine just get 239m on display

Question

I'm using Ubuntu 10.04 with 8Gb memory on DELL 1850 server. And I just got 239m by using "free -d" ...

free command

$ free -m
total       used       free     shared    buffers     cached
Mem:           239        125        114          0         17         41
-/+ buffers/cache:         66        173
Swap:         7811          0       7811

dmidecode

$ sudo dmidecode | grep -P -A5 "Memory\s+Device" | grep Size | grep -v Range 
Size: 2048 MB
Size: 2048 MB
Size: 2048 MB
Size: 2048 MB
Size: No Module Installed
Size: No Module Installed

version info

$ uname -a
Linux segmentfault 2.6.38-8-server #42-Ubuntu SMP Mon Apr 11 03:49:04 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

Answer 1

You should disable "os install mode" in the BIOS setup - enabling this option limits the RAM available to the operating system to 256 MB.