All 32-bit systems have a RAM limit of 3 GB. This limits the maximum amount of RAM a system running on a 32-bit Linux can support. So, even if you have more than 3 GB of ram installed, it will show only 3 GB.

There was a previous workaround which allowed us to use more than 3GB of ram in Linux by installing the server Kernel. This provided us with a kernel which had PAE enabled. This could also be done by recompiling the Linux kernel with PAE enabled. But, this is no longer possible now as the i386-server flavor of Linux is being dropped according to the Ubuntu Wiki.

Thankfully, instead many OEM’s have made a request for a 32-bit Ubuntu with PAE enabled. In response to this, Karmic Koala has options to use PAE. This has been possible due to the meta package linux-generic-pae, which has been added to the Karmic Koala build and allows us to enable PAE for the desktop version.

To enable more than 3 GB, enter this in a terminal. This command will install the PAE packages.

sudo apt-get install linux-generic-pae

Now after restarting the sytem, your Ubuntu should use the full RAM resource of your computer.

For more information on PAE, see the Wikipedia page here ^[1].

For more information on meta packages, see the Ubuntu help page here ^[2].

[ Via Web Upd8 ^[3] ]