> > inxi shows that only 3 GB are available as the TOTAL, although it finds > the 4 GB to be physically installed: > $ sudo inxi -m -x > Memory: RAM: total: 2.88 GiB used: 2.11 GiB (73.2%) > Array-1: capacity: 4 GiB slots: 2 EC: None max module size: 2 GiB note: > est. > Device-1: M1 size: 2 GiB speed: 667 MT/s type: DDR2 > Device-2: M2 size: 2 GiB speed: 667 MT/s type: DDR2 > > It could be a different problem (Windows may calculate RAM differently in different places, where did you check it?). I'd start with a memory map (see Sven Hartge's comment in this thread), also see https://en.wikipedia.org/wiki/E820 A similar tool for Windows is "Rammap".
With 32bit system you would never be able to use 4GB (because part of address space is used for MMIO by PCI-(express) devices). With 64bit address space is much larger, but some ram is used by kernel. Some tools exclude such ram.
