I am on an XPS m1210 laptop that I just upgraded to a full 4gb of RAM. I need to run a very high memory application so I need to use all 4gb, but the bios and Ubuntu only sees ~3.1gb.
I built a custom kernel with PAE enabled, and also tried running ubuntu server (which has pae enabled by default) and both kernels only see the same ~3.1 gb of memory, which leads me to believe that it is some bios level issue - but I could be wrong.
What can I do to utilise the full 4gb of memory? Running lshw tells me that I have bios version A03 (07/28/2006). Running a 64-bit kernel, what would have been the easiest solution, is not an option because the processor Intel T2600 is only 32-bit.
Maybe you need the 64bit version of Ubuntu to see more than 3gb of RAM. 32bit OS's have certain memory limitations. 64 bit OS's can address more memory by design. Windows XP and Vista have the same problem.