Why is more than 3GB of RAM not recognised when using amd64?
I have installed ubuntu 10.04 lts (64bit) on my lenovo thinkpad X60 (Core 2 Duo T5600). I installed 4gb of ram before installing ubuntu, but when I check the available memory in Ubuntu it says that only 2.9gb is installed. I have checked the bios and it shows the full 4gb of ram. Any help with this would be appreciated.